Mercedes - Citan - Workshop Manual - 2002 - 2002

Controller Area Network CAN 507 HO CAN B (ICC)10-28-02 1 These technical training materials are current as of the date noted on the materials, and may be revised or updated without notice. Always check for revised or updated information. To help avoid personal injury to you or others, and to avoid damage to the vehicle on which you are working, you must always refer to the latest Mercedes-Benz Technical Publication and follow all pertinent instructions when testing, diagnosing or making repair. Illustrations and descriptions in this training reference are based on preliminary information and may not correspond to the final US version vehicles. Refer to the official introduction manual and WIS when available. Copyright Mercedes-Benz USA, LLC, 2002 Reproduction by any means or by any information storage and retrieval system or translation in whole or part is not permitted without written authorization from Mercedes-Benz USA, LLC or it's successors. Published by Mercedes-Benz USA, LLC Printed in U. S.A. 2 Objectives • Explain advantages of CAN networks • Explain how CAN networks operate • Describe location of CAN connectors • Explain CAN diagnosis techniques • Provide reference information on other models (reference section at back of handout) 3 What is a CAN System? A CAN system is: • A digital communication link between multiple Electronic Control Modules (ECM) • A 2 wire, bi-directional communication link with data transmitted according to priority • Message specific addressing 4 Advantages • Cost • Improved immunity to electrical interference • Fewer connectors • Fewer pins on control modules • Weight savings • Fewer sensors • Improved diagnosis facilities • Rapid transmission rates 5 Types of CAN Communication Mercedes-Benz uses several CAN networks. Depending on model and year the following may be used. CAN C - Engine CAN (also known as chassis CAN) Fast communication speeds 125 kbps or 500 kbps CAN B - Interior CAN (also known as body CAN) Communication speed 83 kbps Information from CAN C can be sent to control modules on the CAN B or vice versa via the Electronic Ignition Switch (EIS). The EIS is the only control module* that can transfer the messages and is known as the gateway. 6 Without CAN Coolant sensor 1 Control module 1 (e.g. fuel system) Coolant sensor 2 Coolant sensor 3 Control module 2 (e.g. climate control) Control module 3 (e.g. ignition) 7 CAN Bus Sensor 1 Control module 2 Control module 1 Control module 3 Control module 4 Control module 5 Control module 6 8 CAN B Example Controlling R.R. window from L.F. door window switch window switch RR DCM RF DCM window switch LR DCM window switch LF DCM CAN High & Low The CAN wiring consist of 2 wires called CAN High (CAN H) and CAN Low (CAN L). All the control modules are connected in a parallel circuit using either Z splices or plug connector blocks (X30/_). For the remainder of this presentation and shop modules, we will concentrate on the CAN B network as used in W203 / W220). 10 CAN H • CAN-H has a voltage of approx. 0.025 volts when dormant • Rises to base voltage of 0.65 volts when communicating • Data seen as voltage levels going “high” ~0.65volt ~0.025volt 11 CAN L • CAN-L has a voltage of 11.0 volts dormant • Base voltage drops to 4.65 volts when active • Data seen as voltage level going “low” ~11 volt ~4.65 volt 12 CAN B High & Low ~11volt ~4.65volt ~0.65volt ~0.025volt 13 Safety Concept CAN L still communicates (single line operation) CAN H shorted to ground, cannot communicate 14 Wake-up Signal Door switch Rear SAM EIS z...z…z…z…z... WAKE UP !! / Door open • EIS is the master of the CAN • EIS wakes up the control modules on the CAN N70 (Overhead Control Panel) 15 Tools For Diagnosing CAN B h Ohm meter h Volt meter h Oscilloscope h CAN B test harness h SDS 220 589 00 99 30 h WIS Note: The red lead is not always the CAN H 16 W203 CAN B (MY 2001) via N10/1 N73 N70 N22 A1 N72/1 Note: Always refer to the wiring diagram for your model and year. N10/1 X30/4 N69/4 X30/6 N69/2 N32/2 X30/7 2 1 N10/2 A40/3 N32/1 N69/1 N2/7 A35/17 N69/3 1 early late 2 GN/WT GN RD BN BN/BK BN CAN H wires are BN/RD CAN L wires are BN except where indicated 17 W203 CAN B Connector X30/6 h N73 - EIS h N72/1 - UCP h A1 - ICM h N22 - AAC h N70 - OCP h N10/1 - Front SAM 18 W203 CAN B Connector X30/7 h N10/1 - Front SAM h A40/3 - COMAND h A2 - Radio h N69/1 - DCM-FL h N69/3 - DCM-RL h N10/2 - Rear SAM h N32/1 - ESA-FL 19 W203 CAN B Connector X30/4 h N69/2 - DCM-FR h N69/4 - DCM-RR h N2/7 - SRS h A35/17 - TELE AID h N32/2 - ESA-FR 20 CAN B Malfunctions h Shorted CAN B h Constantly active CAN B h Incorrect version coding 21 Shorted CAN B When both the High and Low CAN B are shorted to ground or positive no communication is possible between control units. This can happen if: a. Control unit shorted b. Wiring harness shorted How could we determine if the CAN B is shorted? a. Monitor CAN B voltage out of EIS b. Monitor CAN B oscilloscope pattern out of EIS c. Monitor the DAS (SDS) 22 Constantly Active CAN B CAN B needs to go into a dormant state when the ignition switch is in the 0 position. EIS is the control unit in charge of activation and deactivation of the CAN B. If a control unit in the CAN B keeps sending a signal the EIS will not request the CAN B to go into a dormant state. How can we determine if the CAN B has not gone into a dormant state? a. Monitor CAN B activity with an oscilloscope b. Monitor CAN B voltage 23 Diagnostic Exercise For CAN B The following diagnostic exercise involves a W203 with a shorted control unit. 24 W203 CAN B N73 N70 N22 A1 N72/1 N10/1 X30/4 X30/6 (dash) N69/4 N69/2 X30/7 (left) N32/2 N2/7 N10/2 A40/3 N32/1 N69/1 N69/3 A35/17 25 Diagnostic Exercise For CAN B 26 N73 N70 N22 A1 N72/1 N10/1 X30/4 X30/6 N69/4 N69/2 X30/7 N32/2 N2/7 N10/2 A40/3 N32/1 N69/1 N69/3 A35/17 27 N73 N70 N22 A1 N72/1 N10/1 X30/4 X30/6 Disconnect CAN wire N69/4 N69/2 X30/7 N32/2 N2/7 N10/2 A40/3 N32/1 N69/1 N69/3 A35/17 28 N73 N70 N22 A1 N72/1 N10/1 X30/4 X30/6 Disconnect CAN wire Re-connect CAN wire X30/7 N69/4 N69/2 N32/2 N2/7 N10/2 A40/3 N32/1 N69/1 N69/3 A35/17 Re-connect CAN wires until network instable again 29 N73 N70 N22 A1 N72/1 N10/1 X30/4 X30/6 N69/4 N69/2 X30/7 N32/2 N2/7 N10/2 A40/3 N32/1 N69/1 N69/3 A35/17 30 N73 N70 N22 A1 N72/1 N10/1 X30/4 X30/6 N69/4 N69/2 X30/7 N32/2 N2/7 N10/2 A40/3 N32/1 N69/1 N69/3 A35/17 31 Diagnostic Exercise For CAN B Press the F2 key for a list of control units that the EIS can communicate with 32 Diagnostic Exercise For CAN B 33 Reference Materials for Further Reading WIS documents : GF00.19-P-0001PP SN00.19-P-0004GH GF54.00-P-0004A GF54.00-P-0005A GF54.00-P-0005-01A GF54.00-P-0005-02A GF54.00-P-0005-04A GF54.00-P-0999ZZ Extended vehicle network function Complete networking (163 as of 9/01) Data bus system function CAN data bus, function CAN data bus data telegram CAN data bus specification CAN data bus applications CAN data bus, contents, function description 34 Additional Information for Other Models 35 CAN B Voltages W203, C215 & W220 h CAN H active: 0.65V, dormant: 0.025V h CAN L active: 4.65V, dormant: 11.0V CAN B Voltages W202, C208 & W210 h CAN H active: 1.8V, dormant 0.025V h CAN L active: 3.2V, dormant 4.8V 36 CAN B on W203 with connector X35/2 (Vehicles from approx. 06/02) N73 N70 N22 A1 N72/1 Note: Always refer to the wiring diagram for your model and year. N10/1 Brown and Brown with Red tracer X30/6 N69/2 X30/4 N69/4 X35/2 N32/2 X30/7 N2/7 N10/2 A40/3 N32/1 N69/1 N69/3 A35/17 37 X35/2 Location: Right front sill 38 W220 CAN B N73 N80 N22 A1 N72/1 N10/7 X30/6 Green Band W White Band Y Yellow Band N10/6 N70 W G G X30/4 W N10/8 N69/4 X30/5 Y N69/2 N62 N32/2 A37 A40/3 N22/4 N32/1 N69/1 N69/3 N25/6 N69/5 N88 39 C215 CAN B N73 N80 N22 A1 N72/1 N10/7 X30/6 Green Band W White Band Y Yellow Band N10/6 N70 W G G X30/4 W N10/8 N69/5 X30/5 Y N62 N22/6 N32/2 A37 A40/3 N32/1 N69/1 N88 N69/2 40 Location of X30’s for C215 & W220 X30/6 X30/4 X30/5 41 C215 / W220 Connector X30/6 white band green band h Wires with the green band go to N73 (EIS) h Wires with the white band go to N10/6 (Left SAM) 42 C215 / W220 Connector X30/5 h Wires with the white band go to N10/6 (Left SAM) yellow band h Wires with the yellow band go to X30/4 white band 43 Control Units Connected to X30/6 C215 / W220 h N73 - Electronic Ignition Switch h N80 - Steering Column Module h N22 - Automatic Air Conditioning h A1 - Instrument Cluster h N72/1 - Upper Control Panel h N10/7 - Right SAM h N10/6 - Left SAM 44 Control Units Connected to X30/5 C215 / W220 h A37 - PSE h A40/3 - COMAND h N22/4 - Rear automatic air conditioning h N32/1 - Electric seat adjustment left h N69/1 - Door control module 1 h N69/3 - Door control module 2 h N10/6 - Left SAM 45 Control Units Connected to X30/4 C215 / W220 h N10/8 - Rear SAM h N70 - Overhead control panel (Via N10/8) h N69/2 - Door control module 2 h N69/4 - Door control module 4 h N62 - Parktronics h N32/2 - Electric seat adjustment right h N25/6 - Electric seat adjustment rear h N88 - Tire pressure monitoring h N69/5 - KeyLess Go 46 W202, 208, 210 CAN B • Electronic Ignition Switch EIS - N73 • Signal Acquisition and Actuation Module SAM - N10/1 • Door Control Modules DCM’s - 1 for each door N69/1-4 • Pneumatic System Equipment PSE - A37 • Electronic Seat Adjustment ESA’s - N32/1&2 • Overhead Control Panel OCP - N70 • Lower Control Panel LCP - N72 X30/7 - Right front door sill 47 W210 CAN B R.R.door 48 W202, 208 & 210 CAN B 5V CAN LOW Low Sleep Voltage 4.8V 4V 3V 2V (CAN Message) (CAN Message) Low Awake Voltage 3.2V High Awake Voltage 1.8V 1V CAN HI High Sleep Voltage 0.2V 0V 49 G Class (463) Networking Interior Engine Not on CAN BUS N25/6, Rear seat heater module N30/2, Differential lock module 50 CAN B Diagram for 463 N73 N69/1 A1 A35/11 All CAN H wires are red All CAN L wires are brown except where noted X30/4 N72/1 X30/6 N69/4 CAN H wire black CAN L wire brown X30/7 N69/2 N32/2 N22 N10/2 A40/3 N32/1 N69/3 N10/1 N70 51 463 CAN B Connector Locations X30/6 under drivers dash X30/4 and X30/7 in passenger kick panel CAN wires are labeled with a tag on X30/4 & X30/7 52 463 CAN C Connector X63/4 Location: Right side of center console 53 R230 CAN B , CAN C & D2B CAN- C Gn Gn/Wh N15/5 ESM N15/3 ETC N47-5 ESP 2-wire SBC CAN A73n1 SBC A1 ICM N80 SCM N69/1 DCM-L N10/10 SAM-FL N22 AAC N72 LCP N32/1 ESA-L X11/4 X30/15 CAN- B N51/2 ABC N35/15 MCS-L N73 EIS CAN- B N63/1 DTR X30/18 N3/10 ECM A35/16 MCS-R Br Br / Bk CAN- B Br Br / Bk N70 OCP N69/2 DCM-R N55 SD N2/7 SRS D2B N52 RVC N10/8 Rear SAM N62 PTS N88 TPC N69/5 KG N82/1 BNS A35/8 Tele Aid A2 COMAND A37 PSE CAN B wire colors (except where noted) Br Br / Rd X30/17 CAN C N32/2 ESA-R X30/16 N10/11 SAM-FR CAN B not connected to either CAN 54 R230 CAN B Connector X30/15 Inside driver’s side door sill (next to X30/18) EIS (N73) IC (A1) SCM (N80) DCM-L (N69/1) X3 0/1 SAM-FL (N10/10) 5 AAC (N22) LCP (N72) ESA-L (N32/1) MCS-L (N35/15) 55 R230 CAN B Connector X30/16 Inside passenger side door sill SAM-FR (N10/11) OCP (N70) X 16 30/ DCM-R (N69/2) SD (N55) ESA-R (N32/2) MCS-R (A35/16) 56 R230 CAN B Connector X30/17 Behind passenger seat, next to SAM RVC (N52) SAM-Rear (N10/8) PTS (N62) /17 0 X3 TPC (N88) KG (N69/5) BNS (N82/1) TELE AID (A35/8) COMAND (A2) D2B PSE (A37) 57 R230 CAN C Connector X30/18 Inside driver’s side door sill (next to X30/15) EIS (N73) IC (A1) X3 0/1 SCM (N80) 8 ECM (N3/10) DTR (N63/1) ABC (N5/12) ESM (N15/5) ETC (N15/3) ESP (N47-5) SBC (A73n1) 58 W211 Networking Diagram X11/4 N3/10 N15/5 N15/3 N51 N71 N63/1 N93 X30/5 CAN C N47/5 CAN D N93 CAN B A1 N73 N22 N99 N10/1 N112 X30/6 N80 N112 - Communication Platform (TeleAid) N69/1 X30/4 N25/7 N32/1 N69/2 N69/4 N70 N72 N32/19 N10/11 CAN B N69/3 LCP if vehicle equipped with DTR / SAS N82 N2/7 N72/1 N62 N88 N121 N93/1 M40/1 N10/2 CAN B X30/7 MOST N32/2 N32/22 CAN B CAN C CAN D MOST Interior bus Engine bus Diagnosis bus Audio Bus 59 W211 Networking Legend CAN C N32/19 Left Front Dynamic Seat Control N3/10 ME-SFI Control Module N32/22 Right Front Dynamic Seat Control N15/3 ETC - Electronic Transmission Control N62 PTS - Parktronic Control N15/5 ESM - Electronic Selector Module N69/1 DCM - Left Front Door Control Module N47/5 ESP - Electronic Stability Program N69/2 DCM - Right Front Door Control Module N51 SAS - Semi-Active Air Suspension N69/3 DCM - Left Rear Door Control Module N63/1 DTR - Distronic Control Module N69/4 DCM - Right Rear Door Control Module N71 HRA - Headlamp Range Adjustment N70 OCP - Overhead Control Panel N93 CGW - Central Gateway Module N72/1 UCP - Upper Control Panel N82 BCM - Battery Control Module CAN B M40/1 Pneumatic Pump of Dynamic Seat N88 TPC - Tire Pressure Monitor Control Module N2/7 Supplemental Restraint System N93/1 AGW - Audio Gateway Control Module N10/1 SAM-D - Driver-side N99 SWH - Steering Wheel Heater N10/2 SAM-R - Rear N121 RTL - Remote Trunk Locking Control Module N10/11 SAM-P - Passenger-side CAN C & B N22 AAC - Automatic Air Conditioning Control A1 ICM - Instrument Cluster N25/7 HS and Seat Ventilation Control Module N73 EIS - Electronic Ignition Switch Control N32/1 ESA - Left Front Seat Adjustment N80 SCM - Steering Column Module N32/2 ESA - Right Front Seat Adjustment N93 CGM - Central Gateway Module 60 CAN C Connector (X30/5) Location: Drivers rocker panel wiring trough 61 CAN B Connector (X30/4) Location: Right side passenger footwell 62 CAN B Connector (X30/6) Location: Passenger side HVAC case 63 CAN B Connector (X30/7) Location: Drivers rocker panel wiring trough 64 SAM-Rear (N10/2) Several control modules are connected to the CAN B network via N10/2. Location: Left side trunk 65 W211 CAN D • Is the diagnostic link between Central Gateway Module (N93), Communications Platform (N112) and SDS / DAS CAN Low - Pin 14 (GN) CAN High - Pin 6 (GN/WT) CAN Low • CAN D voltage High = 2.5v Low = 2.5v • CAN D voltage awake High = activity to 3.5v Low = activity to 1.5v • All modules on CAN B are diagnosed by SDS / DAS through CAN D X11/4 9 16 1 8 CAN High N93 N112 66