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Module Communications Network: Diagnosis Ford Focus I facelift

Communication Devices 23 illustrations ~4774 words

Inspection and Verification

  1. Verify the customer concern.
  2. Visually inspect the following for obvious signs of electrical damage. VISUAL INSPECTION CHART Electrical Battery junction box (BJB) fuse(s): 9 (20A) (no communication with PCM) 20 (10A) (no communication with PCM) 29 (10A) (no communication with ABS module) Central junction box (CJB) fuse(s): 35 (7.5A) (no communication with instrument cluster [IC]) 48 (10A) (no power to the scan tool) 57 (7.5A) (no communication with IC) 60 (7.5A) (no communication with restraints control module [RCM]) 61 (7.5A) (no communication with IC) Data link connector (DLC) Circuitry
  3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
  4. If the cause is not visually evident, connect the scan tool to the DLC. If the scan tool does not communicate with the VCM: Check the VCM connection to the vehicle. Check the scan tool connection to the VCM. Go to «Pinpoint Test G»(ref-278282-S12123590692008012400000) , to diagnose no power to the scan tool.
  5. Carry out the network test. If the network test passes, retrieve and record the continuous memory DTCs and proceed to Step 6 . If the network test fails, go to «Symptom Chart»(ref-278282-S20046810842008012400000) to identify the module not communicating.
  6. If the DTCs retrieved are related to the concern, go to «COMMUNICATION NETWORK DTC CHART»(ref-278282-S40499105082008012400000) . For all other DTCs, refer to «MULTIFUNCTION ELECTRONIC MODULES»(ref-278283) article.
  7. If no DTCs related to the concern are retrieved, go to «Symptom Chart»(ref-278282-S20046810842008012400000) .

Note. DTC U1900 will set in a module that is reporting a communication fault from another module on the data bus. The module that reports the fault is not the problem module.

DTCDescriptionSourceAction
U0073Control Module Communication Bus OffRestraints control module (RCM)DTC U0073 indicates the module could not communicate on the network at a point in time. The fault is currently not present. CLEAR the DTC. REPEAT the network test with the scan tool.
U1900CAN Communication Bus Fault-Receive ErrorInstrument cluster (IC)For module that failed network test, go to Symptom Chart .
U1900CAN Communication Bus Fault-Receive ErrorABS moduleFor module that failed network test, go to Symptom Chart .
U1900CAN Communication Bus Fault-Receive ErrorRCMFor module that failed network test, go to Symptom Chart .
U2012Communication Bus ErrorABS moduleGo to Pinpoint Test D .
U2023Fault Received From External NodeABS moduleRETRIEVE and FOLLOW non-network DTCs from other modules. REFER to MULTIFUNCTION ELECTRONIC MODULES article.

COMMUNICATION NETWORK DTC CHART

Symptom Chart

ConditionPossible SourcesAction
The PCM does not respond to the scan tool or no high speed controller area network (HS-CAN) communicationFuse Circuitry PCM ABS module Restraints control module (RCM) Occupant classification system module (OCSM) Instrument cluster (IC)Go to Pinpoint Test A .
The generic electronic module (GEM) does not respond to the scan toolFuse Circuitry GEMGo to Pinpoint Test B .
The restraints control module (RCM) does not respond to the scan toolFuse Circuitry RCMGo to Pinpoint Test C .
The ABS module does not respond to the scan toolFuse Circuitry ABS moduleGo to Pinpoint Test D .
The instrument cluster (IC) does not respond to the scan toolFuse Circuitry ICGo to Pinpoint Test E .
No high speed controller area network (HS-CAN) communication, all modules are not respondingFuse Circuitry PCM ABS module RCM OCSM ICGo to Pinpoint Test A .
No International Standards Organization (ISO) 9141 network communicationCircuitry GEMGo to Pinpoint Test F .
No power to the scan toolFuse Circuitry Scan toolGo to Pinpoint Test G .

Symptom Chart

Pinpoint Test A: The PCM Does Not Respond To The Scan Tool or No High Speed Controller Area Network (HS-CAN) Communication

Refer to SYSTEM WIRING DIAGRAMS article, Module Communications Network for schematic and connector information.

Refer to SYSTEM WIRING DIAGRAMS article, Electronic Engine Controls for schematic and connector information.

Note. Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

Scheme 3

Scheme 3: PINPOINT TEST A: THE PCM DOES NOT RESPOND TO THE SCAN TOOL OR NO HIGH SPEED CONTROLLER AREA NETWORK
Scheme 3: PINPOINT TEST A: THE PCM DOES NOT RESPOND TO THE SCAN TOOL OR NO HIGH SPEED CONTROLLER AREA NETWORK

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Scheme 6

Scheme 6
Scheme 6
  1. A1 CHECK THE DATA LINK CONNECTOR (DLC) PINS FOR DAMAGE NOTE: Most faults are due to connector and/or wiring concerns. Carry out a thorough inspection and verification before proceeding with the Pinpoint Test. Key in OFF position. Disconnect the scan tool cable from the DLC. Inspect DLC pins 6 and 14 for damage. Are DLC pins 6 and 14 OK? YES : Go to A2 . NO : REPAIR the DLC as necessary. CLEAR the DTCs. REPEAT the network test with the scan tool.
  2. A2 CHECK THE HS-CAN TERMINATION RESISTANCE Key in OFF position. NOTE: Failure to disconnect the battery will result in false resistance readings. Disconnect the battery ground cable. Disconnect the scan tool cable from the DLC. Measure the resistance between the DLC C251-6, circuit 4-EC7 (GY/RD), harness side and the DLC C251-14, circuit 5-EC7 (BU/RD), harness side. Is the resistance between 54 and 66 ohms? YES : Go to A5 . NO : Go to A3 .
  3. A3 CHECK THE HS-CAN TERMINATION RESISTOR Measure the resistance between the DLC C251-6, circuit 4-EC7 (GY/RD), harness side and the DLC C251-14, circuit 5-EC7 (BU/RD), harness side. Is the resistance between 108 and 132 ohms? YES : Go to A9 . NO : Go to A4 .
  4. A4 CHECK THE HS-CAN (+) AND HS-CAN (-) CIRCUITS FOR A SHORT TOGETHER Measure the resistance between the DLC C251-6, circuit 4-EC7 (GY/RD), harness side and the DLC C251-14, circuit 5-EC7 (BU/RD), harness side. Is the resistance less than 5 ohms? YES : Go to A10 . NO : Go to A9 .
  5. A5 CHECK THE HS-CAN (+) AND HS-CAN (-) CIRCUITS FOR A SHORT TO GROUND Measure the resistance between the DLC C251-6, circuit 4-EC7 (GY/RD), harness side and ground; and between the DLC C251-14, circuit 5-EC7 (BU/RD), harness side and ground. Are the resistances greater than 1,000 ohms? YES : Go to A6 . NO : Go to A15 .
  6. A6 CHECK THE HS-CAN (+) AND HS-CAN (-) CIRCUITS FOR A SHORT TO VOLTAGE Connect the battery ground cable. Key in ON position. Measure the voltage between the DLC C251-6, circuit 4-EC7 (GY/RD), harness side and ground; and between the DLC C251-14, circuit 5-EC7 (BU/RD), harness side and ground. Is the voltage greater than 6 volts? YES : REPAIR the circuit. CLEAR the DTCs. REPEAT the network test with the scan tool. NO : Go to A7 .
  7. A7 CHECK THE PCM VOLTAGE SUPPLY Key in OFF position. Disconnect: PCM C175b Key in ON position. Measure the voltage between the PCM, harness side and ground as follows: Connector-Pin Circuit C175b-35 15-RE8 (GN/YE) C175b-36 15-RE8A (GN/YE) C175b-45 30-RE8 (RD) Are the voltages greater than 10 volts? YES : Go to A8 . NO : VERIFY the battery junction box (BJB) fuse 20 (10A) and fuse 9 (20A) is OK. If OK, REPAIR the circuit in question. CLEAR the DTCs. REPEAT the network test with the scan tool.
  8. A8 CHECK THE PCM GROUND CIRCUITS Key in OFF position. Measure the resistance between the PCM, harness side and ground as follows: Connector-Pin Circuit C175b-47 91-RE8 (BK/YE) C175b-48 91-RE8 (BK/YE) C175b-49 91-RE8 (BK/YE) Are the resistances less than 5 ohms? YES : Go to A20 . NO : REPAIR the circuit. CLEAR the DTCs. REPEAT the network test with the scan tool.
  9. A9 CHECK THE HS-CAN CIRCUITS BETWEEN THE PCM AND THE DLC FOR AN OPEN Measure the resistance between the PCM C175b-11, circuit VDB04 (WH/BU), harness side and the DLC C251-6, circuit VDB04 (WH/BU), harness side. Measure the resistance between the PCM C175b-23, circuit VDB05 (WH), harness side and the DLC C251-14, circuit VDB05 (WH), harness side. Are the resistances less than 5 ohms? YES : Go to A20 . NO : REPAIR the circuit in question. CLEAR the DTCs. REPEAT the network test with the scan tool.
  10. A10 CHECK THE HS-CAN (+) AND HS-CAN (-) CIRCUITS FOR A SHORT TOGETHER WITH THE PCM DISCONNECTED Disconnect: PCM C175b Measure the resistance between the DLC C251-6, circuit 4-EC7 (GY/RD), harness side and the DLC C251-14, circuit 5-EC7 (BU/RD), harness side. Is the resistance less than 5 ohms? YES : Go to A11 . NO : Go to A20 .
  11. A11 CHECK THE HS-CAN (+) AND HS-CAN (-) CIRCUITS FOR A SHORT TOGETHER WITH THE ABS MODULE DISCONNECTED Disconnect: ABS Module C135 (With Traction Control) Disconnect: ABS Module C155 (Without Traction Control) Measure the resistance between the DLC C251-6, circuit 4-EC7 (GY/RD), harness side and the DLC C251-14, circuit 5-EC7 (BU/RD), harness side. Is the resistance less than 5 ohms? YES : Go to A12 . NO : Go to A21 .
  12. A12 CHECK THE HS-CAN (+) AND HS-CAN (-) CIRCUITS FOR A SHORT TOGETHER WITH THE INSTRUMENT CLUSTER (IC) DISCONNECTED Disconnect: IC C2220 Measure the resistance between the DLC C251-6, circuit 4-EC7 (GY/RD), harness side and the DLC C251-14, circuit 5-EC7 (BU/RD), harness side. Is the resistance less than 5 ohms? YES : Go to A13 . NO : Go to A22 .
  13. A13 CHECK THE HS-CAN (+) AND HS-CAN (-) CIRCUITS FOR A SHORT TOGETHER WITH THE RESTRAINTS CONTROL MODULE (RCM) DISCONNECTED Depower the supplemental restraint system (SRS). Refer to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-278281) article. Disconnect: RCM C2041b Measure the resistance between the DLC C251-6, circuit VDB04 (WH/BU), harness side and the DLC C251-14, circuit VDB05 (WH), harness side. Is the resistance less than 5 ohms? YES : Go to A14 . NO : Go to A23 .
  14. A14 CHECK THE HS-CAN (+) AND HS-CAN (-) CIRCUITS FOR A SHORT TOGETHER WITH THE OCCUPANT CLASSIFICATION SYSTEM MODULE (OCSM) DISCONNECTED Disconnect: OCSMC3043 Measure the resistance between the DLC C251-6, circuit VDB04 (WH/BU), harness side and the DLC C251-14, circuit VDB05 (WH), harness side. Is the resistance less than 5 ohms? YES : REPAIR the circuit. CONNECT all modules. REPOWER the SRS. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-278281) article. CLEAR the DTCs. REPEAT the network test with the scan tool. NO : Go to A24 .
  15. A15 CHECK THE HS-CAN (+) AND HS-CAN (-) CIRCUITS FOR A SHORT TO GROUND WITH THE PCM DISCONNECTED Disconnect: PCM C175b Measure the resistance between the DLC C251-6, circuit 4-EC7 (GY/RD), harness side and ground; and between the DLC C251-14, circuit 5-EC7 (BU/RD), harness side and ground. Are the resistances greater than 1,000 ohms? YES : Go to A20 . NO : Go to A16 .
  16. A16 CHECK THE HS-CAN (+) AND HS-CAN (-) CIRCUITS FOR A SHORT TO GROUND WITH THE ABS MODULE DISCONNECTED Disconnect: ABS Module C135 Measure the resistance between the DLC C251-6, circuit 4-EC7 (GY/RD), harness side and ground; and between the DLC C251-14, circuit 5-EC7 (BU/RD), harness side and ground. Are the resistances greater than 1,000 ohms? YES : Go to A21 . NO : Go to A17 .
  17. A17 CHECK THE HS-CAN (+) AND HS-CAN (-) CIRCUITS FOR A SHORT TO GROUND WITH THE INSTRUMENT CLUSTER (IC) DISCONNECTED Disconnect: IC C2220 Measure the resistance between the DLC C251-6, circuit 4-EC7 (GY/RD), harness side and ground; and between the DLC C251-14, circuit 5-EC7 (BU/RD), harness side and ground. Are the resistances greater than 1,000 ohms? YES : Go to A22 . NO : Go to A18 .
  18. A18 CHECK THE HS-CAN (+) AND HS-CAN (-) CIRCUITS FOR A SHORT TO GROUND WITH THE RESTRAINTS CONTROL MODULE (RCM) DISCONNECTED Depower the supplemental restraint system (SRS). Refer to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-278281) article. Disconnect: RCM C2041b Measure the resistance between the DLC C251-6, circuit VDB04 (WH/BU), harness side and the DLC C251-14, circuit VDB05 (WH), harness side. Are the resistances greater than 1,000 ohms? YES : Go to A23 . NO : Go to A19 .
  19. A19 CHECK THE HS-CAN (+) AND HS-CAN (-) CIRCUITS FOR A SHORT TO GROUND WITH THE OCCUPANT CLASSIFICATION SYSTEM MODULE (OCSM) DISCONNECTED Disconnect: OCSM C3043 Measure the resistance between the DLC C251-6, circuit VDB04 (WH/BU), harness side and the DLC C251-14, circuit VDB05 (WH), harness side. Are the resistances greater than 1,000 ohms? YES : Go to A24 . NO : REPAIR the circuit. CONNECT all modules. REPOWER the SRS. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-278281) article. CLEAR the DTCs. REPEAT the network test with the scan tool.
  20. A20 CHECK FOR CORRECT PCM OPERATION Disconnect all the PCM connectors. Check for: corrosion damaged pins pushed-out pins Connect all the PCM module connectors and make sure they seat correctly. Operate the system and verify the concern is still present. Is the concern still present? YES : INSTALL a new PCM. REFER to «ELECTRONIC ENGINE CONTROLS»(ref-278253) article. CLEAR the DTCs. REPEAT the network test with the scan tool. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the network test with the scan tool.
  21. A21 CHECK FOR CORRECT ABS MODULE OPERATION Disconnect the ABS module connector. Check for: corrosion damaged pins pushed-out pins Connect the ABS module connector and make sure it seats correctly. Verify the concern is still present. Is the concern still present? YES : INSTALL a new ABS module. REFER to «VEHICLE DYNAMIC SYSTEMS»(ref-278290) article. CLEAR the DTCs. REPEAT the network test with the scan tool. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the network test with the scan tool.
  22. A22 CHECK FOR CORRECT IC OPERATION Disconnect the IC connector. Check for: corrosion damaged pins pushed-out pins Connect the IC connector and make sure it seats correctly. Operate the system and verify the concern is still present. Is the concern still present? YES : INSTALL a new IC. REFER to «INSTRUMENT CLUSTER»(ref-278286) article. CLEAR the DTCs. REPEAT the network test with the scan tool. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the network test with the scan tool.
  23. A23 CHECK FOR CORRECT RCM OPERATION Disconnect all the RCM connectors. Check for: corrosion damaged pins pushed-out pins Connect all the RCM connectors and make sure they seat correctly. Verify the concern is still present. Is the concern still present? YES : INSTALL a new RCM. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-278281) article. CLEAR the DTCs. REPEAT the network test with the scan tool. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. REPOWER the SRS. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-278281) article. CLEAR the DTCs. REPEAT the network test with the scan tool.
  24. A24 CHECK FOR CORRECT OCSM OPERATION Disconnect the OCSM connector. Check for: corrosion damaged pins pushed-out pins Connect the OCSM connector and make sure it seats correctly. Verify the concern is still present. Is the concern still present? YES : INSTALL a new OCSM. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-278281) article. CLEAR the DTCs. REPEAT the network test with the scan tool. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. REPOWER the SRS. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-278281) article. CLEAR the DTCs. REPEAT the network test with the scan tool.

Pinpoint Test B: The Generic Electronic Module (GEM) Does Not Respond To The Scan Tool

Refer to SYSTEM WIRING DIAGRAMS article, Module Communications Network for schematic and connector information.

Refer to SYSTEM WIRING DIAGRAMS article, Multifunction Control Modules for schematic and connector information.

Note. Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

Scheme 7

Scheme 7: PINPOINT TEST B: THE GENERIC ELECTRONIC MODULE (GEM) DOES NOT RESPOND TO THE SCAN TOOL
Scheme 7: PINPOINT TEST B: THE GENERIC ELECTRONIC MODULE (GEM) DOES NOT RESPOND TO THE SCAN TOOL

Scheme 8

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Scheme 11

Scheme 11
Scheme 11
  1. B1 CHECK THE GEM VOLTAGE SUPPLY CIRCUITS FOR AN OPEN Key in OFF position. Disconnect: GEM C201c Measure the voltage between the GEM 201c-1, circuit 29-AA17 (OG/WH), harness side and ground; and between the GEM 201c-5, circuit 29-DK20 (OG/GN), harness side and ground. Are the voltages greater than 10 volts? YES : Go to B2 . NO : VERIFY the central junction box (CJB) fuse 63 (20A) and fuse 32 (15A) are OK. If OK, REPAIR the circuit. CLEAR the DTCs. REPEAT the network test with the scan tool.
  2. B2 CHECK THE GEM GROUNDS Disconnect: GEM C201d Measure the resistance between the GEM C201d-1, circuit 91-DK20 (BK/RD), harness side and ground. Is the resistance less than 5 ohms? YES : Go to B3 . NO : REPAIR the circuit. CLEAR the DTCs. REPEAT the network test with the scan tool.
  3. B3 CHECK THE GEM GROUNDS Disconnect: GEM C201a Measure the resistance between the GEM C201a-5, circuit 31-DK20 (BK), harness side and ground. Is the resistance less than 5 ohms? YES : Go to B4 . NO : REPAIR the circuit. CLEAR the DTCs. REPEAT the network test with the scan tool.
  4. B4 CHECK CIRCUIT 8-EE9 (WH/GN) FOR A SHORT TO GROUND Measure the resistance between the data link connector (DLC) C251-7, circuit 8-EE9 (WH/GN), harness side and ground. Is the resistance greater than 10,000 ohms? YES : Go to B5 . NO : REPAIR the circuit. CLEAR the DTCs. REPEAT the network test with the scan tool.
  5. B5 CHECK CIRCUIT 8-EE9 (WH/GN) FOR A SHORT TO VOLTAGE Key in ON position. Measure the voltage between the DLC C251-7, circuit 8-EE9 (WH/GN), harness side and ground. Is any voltage indicated? YES : REPAIR the circuit. CLEAR the DTCs. REPEAT the network test with the scan tool. NO : Go to B6 .
  6. B6 CHECK CIRCUIT 8-EE9 (WH/GN) BETWEEN THE DLC AND THE GEM FOR AN OPEN Measure the resistance between the DLC C251-7, circuit 8-EE9 (WH/GN), harness side and the GEM C201d-16, circuit 8-EE9 (WH/GN), harness side. Is the resistance less than 5 ohms? YES : Go to B7 . NO : REPAIR the circuit. CLEAR the DTCs. REPEAT the network test with the scan tool.
  7. B7 CHECK FOR CORRECT GEM OPERATION Disconnect all the GEM connectors. Check for: corrosion damaged pins pushed-out pins Connect all the GEM connectors and make sure they seat correctly. Operate the system and verify the concern is still present. Is the concern still present? YES : INSTALL a new GEM. REFER to «MULTIFUNCTION ELECTRONIC MODULES»(ref-278283) article. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the data link diagnostics test. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the network test with the scan tool.

Pinpoint Test C: The Restraints Control Module (RCM) Does Not Respond To The Scan Tool

Refer to SYSTEM WIRING DIAGRAMS article, Module Communications Network for schematic and connector information.

Refer to SYSTEM WIRING DIAGRAMS article, Supplemental Restraint System for schematic and connector information.

WARNINGNever probe the electrical connectors on safety belt buckle/retractor pretensioners or adaptive load limiting retractors. Failure to follow this instruction may result in the accidental deployment of the safety belt pretensioners or adaptive load limiting retractors, which increases the risk of serious personal injury or death.
WARNINGNever probe the electrical connectors on air bag, safety canopy or side air curtain modules. Failure to follow this instruction may result in the accidental deployment of these modules, which increases the risk of serious personal injury or death.

Note. Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

Note. The supplemental restraints system (SRS) must be fully operational and free of faults before releasing the vehicle to the customer.

  1. C1 CHECK THE RCM C2041B PINS 19 AND 20 FOR DAMAGE Key in OFF position. Depower the SRS. Refer to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-278281) article. Disconnect: RCM C2041a and C2041b Inspect the RCM C2041b, harness side and RCM C2041b, component side, pins 19 and 20 for damage. Are the RCM C2041b and RCM C2041b pins 19 and 20 OK? YES : Go to C2 . NO : REPAIR the RCM connector pins as necessary. REPOWER the SRS. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-278281) article. CLEAR the DTCs. REPEAT the network test with the scan tool.

Scheme 12

Scheme 12
Scheme 12
  1. C2 CHECK THE IGNITION CIRCUIT 15-JA10 (GN/OG) FOR AN OPEN Deactivate the SRS. Refer to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-278281) article. Key in ON position. Measure the voltage between the RCM C2041b-24, circuit 15-JA10 (GN/OG), harness side and ground. Is the voltage greater than 10 volts? YES : Go to C3 . NO : VERIFY the central junction box (CJB) fuse 60 (7.5A) is OK. If OK, REPAIR circuit 15-JA10 (GN/OG). REACTIVATE the SRS. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-278281) article. CLEAR the DTCs. REPEAT the network test with the scan tool.
  1. C3 CHECK THE RCM CASE GROUND Key in OFF position. Measure the resistance between the RCM case and a good sheet metal ground near the RCM. Is the resistance less than 25 ohms? YES : Go to C4 . NO : REPAIR the RCM case ground as necessary. REACTIVATE the SRS. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-278281) article. CLEAR the DTCs. REPEAT the network test with the scan tool.

Scheme 13

Scheme 13
Scheme 13
  1. C4 CHECK THE HS-CAN CIRCUITS BETWEEN THE RCM AND THE DLC FOR AN OPEN Measure the resistance between the RCM C2041b-19, circuit 4-EC18 (GY/BK), harness side and the DLC C251-6, circuit 4-EC7 (GY/RD), harness side; and between the RCM C2041b-20, circuit 5-EC18 (BU/BK), harness side and the DLC C251-14, circuit 5-EC7 (BU/RD), harness side. Are the resistances less than 0.5 ohm? YES : Go to C5 . NO : REPAIR the circuit in question. REACTIVATE the SRS. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-278281) article. CLEAR the DTCs. REPEAT the network test with the scan tool.
  1. C5 CHECK FOR CORRECT RCM OPERATION Disconnect all the RCM connectors. Check for: corrosion damaged pins pushed-out pins Connect all the RCM connectors and make sure they seat correctly. Operate the system and verify the concern is still present. Is the concern still present? YES : INSTALL a new RCM. REACTIVATE the SRS. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-278281) article. CLEAR the DTCs. REPEAT the network test with the scan tool. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. REACTIVATE the SRS. REFER to «SUPPLEMENTAL RESTRAINT SYSTEM»(ref-278281) article. CLEAR the DTCs. REPEAT the network test with the scan tool.

Pinpoint Test D: The ABS Module Does Not Respond To The Scan Tool

Refer to SYSTEM WIRING DIAGRAMS article, Module Communications Network for schematic and connector information.

Refer to SYSTEM WIRING DIAGRAMS article, Vehicle Dynamic Systems for schematic and connector information.

Note. Use the correct probe adapter(s) when taking measurements. Failure to use the correct probe adapter(s) may damage the connector.

Scheme 14

Scheme 14: PINPOINT TEST D: THE ABS MODULE DOES NOT RESPOND TO THE SCAN TOOL
Scheme 14: PINPOINT TEST D: THE ABS MODULE DOES NOT RESPOND TO THE SCAN TOOL

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Scheme 19
  1. D1 CHECK VOLTAGE TO THE ABS MODULE Key in OFF position. Disconnect: ABS Module C135 (With Traction Control) Disconnect: ABS Module C155 (Without Traction Control) Key in ON position. If equipped with traction control, measure the voltage between the ABS module C135-4, circuit 15-CF6 (GN/YE), harness side and ground. If not equipped with traction control, measure the voltage between the ABS module C155-20, circuit 15-CF6 (GN/YE), harness side and ground. Are the voltages greater than 10 volts? YES : Go to D2 . NO : VERIFY the battery junction box (BJB) fuse 29 (10A) is OK. If OK, REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
  2. D2 CHECK THE ABS MODULE GROUND(S) Key in OFF position. If equipped with traction control, measure the resistance between the ABS module C135-16, circuit 31-CF6 (BK), harness side and ground; and between the ABS module C135-47, circuit 31-CF13 (BK), harness side and ground. If not equipped with traction control, measure the resistance between the ABS module C155-26, circuit 31-CF6 (BK), harness side and ground. Are the resistances less than 5 ohms? YES : Go to D3 . NO : REPAIR the circuit(s) in question. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
  3. D3 CHECK THE HS-CAN CIRCUITS BETWEEN THE ABS MODULE AND THE DATA LINK CONNECTOR (DLC) FOR AN OPEN If equipped with traction control, measure the resistance between the ABS module CAN (+) C135-11, circuit 4-EC9 (GY), harness side and the DLC C251-6, circuit 4-EC7 (GY/RD), harness side, and between the ABS module CAN (-) C135-15, circuit 5-EC9 (BU), harness side and the DLC C251-14, circuit 5-EC7 (BU/RD), harness side. If not equipped with traction control, measure the resistance between the ABS module CAN (+) C155-23, circuit 4-EC9 (GY), harness side and the DLC C251-6, circuit 4-EC7 (GY/RD), harness side, and between the ABS module CAN (-) C155-21, circuit 5-EC9 (BU), harness side and the DLC C251-14, circuit 5-EC7 (BU/RD), harness side. Are the resistances less than 5 ohms? YES : Go to D4 . NO : REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the data link diagnostics test.
  4. D4 CHECK FOR CORRECT ABS MODULE OPERATION Disconnect the ABS module connector. Check for: corrosion damaged pins pushed-out pins Connect the ABS module connector and make sure it seats correctly. Operate the system and verify the concern is still present. Is the concern still present? YES : INSTALL a new ABS module. REFER to «VEHICLE DYNAMIC SYSTEMS»(ref-278290) article. CLEAR the DTCs. REPEAT the network test with the scan tool. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the network test with the scan tool.

Pinpoint Test E: The Instrument Cluster (IC) Does Not Respond To The Scan Tool

Refer to SYSTEM WIRING DIAGRAMS article, Module Communications Network for schematic and connector information.

Refer to SYSTEM WIRING DIAGRAMS article, Instrument Cluster for schematic and connector information.

Note. Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

Scheme 20

Scheme 20: PINPOINT TEST E: THE INSTRUMENT CLUSTER (IC) DOES NOT RESPOND TO THE SCAN TOOL
Scheme 20: PINPOINT TEST E: THE INSTRUMENT CLUSTER (IC) DOES NOT RESPOND TO THE SCAN TOOL

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Scheme 24
Scheme 24
  1. E1 CHECK CIRCUIT 29-GG14 (OG) FOR VOLTAGE Key in OFF position. Disconnect: IC C2220 Measure the voltage between the IC C2220-28, circuit 29-GG14 (OG), harness side and ground. Is the voltage greater than 10 volts? YES : Go to E2 . NO : VERIFY the central junction box (CJB) fuse 35 (7.5A) is OK. If OK, REPAIR the circuit. TEST the system for normal operation.
  2. E2 CHECK CIRCUIT 75-GG14 (YE/BU) FOR VOLTAGE Key in ACCESSORY position. Measure the voltage between the IC C2220-6, circuit 75-GG14 (YE/BU), harness side and ground. Is the voltage greater than 10 volts? YES : Go to E3 . NO : VERIFY the CJB fuse 57 (7.5A) is OK. If OK, REPAIR the circuit. TEST the system for normal operation.
  3. E3 CHECK CIRCUIT 15-GG14 (GN/RD) FOR VOLTAGE Key in ON position. Measure the voltage between the IC C2220-12, circuit 15-GG14 (GN/RD), harness side and ground. Is the voltage greater than 10 volts? YES : Go to E4 . NO : VERIFY the CJB fuse 61 (7.5A) is OK. If OK, REPAIR the circuit. TEST the system for normal operation.
  4. E4 CHECK CIRCUIT 91-GG14 (BK/OG) FOR AN OPEN Key in OFF position. Measure the resistance between the IC C2220-30, circuit 91-GG14 (BK/OG), harness side and ground. Is the resistance less than 5 ohms? YES : Go to E5 . NO : REPAIR the circuit. TEST the system for normal operation.
  5. E5 CHECK THE HS-CAN CIRCUITS BETWEEN THE DATA LINK CONNECTOR (DLC) AND THE IC FOR AN OPEN Measure the resistance between the DLC C251-6, circuit 4-EC7 (GY/RD), harness side and the IC C2220-31, circuit 4-EC7B (GY/RD), harness side; and between the DLC C251-14, circuit 5-EC7 (BU/RD), harness side and the IC C2220-15, circuit 5-EC7B (BU/RD), harness side. Are the resistances less than 5 ohms? YES : Go to E6 . NO : REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the data link diagnostics test.
  6. E6 CHECK FOR CORRECT IC OPERATION Disconnect the IC connector. Check for: corrosion damaged pins pushed-out pins Connect the IC connector and make sure it seats correctly. Operate the system and verify the concern is still present. Is the concern still present? YES : INSTALL a new IC. REFER to «INSTRUMENT CLUSTER»(ref-278286) article. CLEAR the DTCs. REPEAT the network test with the scan tool. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the network test with the scan tool.

Pinpoint Test F: No International Standards Organization (ISO) 9141 Communications Network Communication

Refer to SYSTEM WIRING DIAGRAMS article, Module Communications Network for schematic and connector information.

PINPOINT TEST F: NO INTERNATIONAL STANDARDS ORGANIZATION (ISO) 9141 NETWORK COMMUNICATION

Note. Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

Scheme 25

Scheme 25: PINPOINT TEST F: NO INTERNATIONAL STANDARDS ORGANIZATION (ISO) 9141 NETWORK COMMUNICATION
Scheme 25: PINPOINT TEST F: NO INTERNATIONAL STANDARDS ORGANIZATION (ISO) 9141 NETWORK COMMUNICATION
  1. F1 CHECK THE DLC PINS FOR DAMAGE NOTE: Most faults are due to connector and/or wiring concerns. Carry out a thorough inspection and verification before proceeding with the Pinpoint Test. Key in OFF position. Disconnect the scan tool cable from the DLC. Inspect DLC pin 7 for damage. Is DLC pin 7 OK? YES : Go to F2 . NO : REPAIR the DLC as necessary. CLEAR the DTCs. REPEAT the network test with the scan tool.
  2. F2 CHECK THE ISO 9141 CIRCUIT BETWEEN THE DLC AND THE GEM FOR AN OPEN Disconnect: GEM C201d Measure the resistance between the DLC C251-7, circuit 8-EE9 (WH/GN), harness side and the GEM C201d-16, circuit 8-EE9 (WH/GN), harness side. Is the resistance less than 5 ohms? YES : Go to F3 . NO : REPAIR the circuit. CLEAR the DTCs. REPEAT the network test with the scan tool.
  3. F3 CHECK THE ISO 9141 NETWORK FOR A SHORT TO GROUND Measure the resistance between the DLC C251-7, circuit 8-EE9 (WH/GN), harness side and ground. Is the resistance greater than 10,000 ohms? YES : Go to F4 . NO : REPAIR the circuit. CLEAR the DTCs. REPEAT the network test with the scan tool.
  4. F4 CHECK THE ISO CIRCUIT FOR A SHORT TO VOLTAGE Key in ON position. Measure the voltage between the DLC C251-7, circuit 8-EE9 (WH/GN), harness side and ground. Is any voltage indicated? YES : REPAIR the circuit. CLEAR the DTCs. REPEAT the network test with the scan tool. NO : Go to F5 .
  5. F5 CHECK FOR CORRECT GEM OPERATION Disconnect all the GEM connectors. Check for: corrosion damaged pins pushed-out pins Connect all the GEM connectors and make sure they seat correctly. Operate the system and verify the concern is still present. Is the concern still present? YES : INSTALL a new GEM. REFER to «MULTIFUNCTION ELECTRONIC MODULES»(ref-278283) article. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the data link diagnostics test. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the network test with the scan tool.

Pinpoint Test G: No Power To The Scan Tool

Refer to SYSTEM WIRING DIAGRAMS article, Module Communications Network for schematic and connector information.

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