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Pinpoint Test R: Abs Module Communication Concern With The RCM

  1. Refer to Module Communications Network for schematic and connector information.

    Normal Operation and Fault Conditions 

    With the ignition ON, the RCM sends messages to the GWM over the HS-CAN2, the GWM relays these messages to the ABS module over the FD-CAN. If the ABS module does not receive these messages within a certain time frame, the ABS module sets a DTC. For information on the messages sent to the ABS module by the RCM, REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description .

    DTC Fault Trigger Conditions 

    DTC Description Fault Trigger Condition
    ABS C102E:48 Stability Control System: Supervision Software Failure Sets if the RCM unable to reach an operational state.
    ABS U0151:87 Lost Communication With Restraints Control Module: Missing Message Sets if the time allotted for stability sensor messages expires before the ABS module receives any stability sensor messages.
    ABS U0452:00 Invalid Data Received From Restraints Control Module: No Sub Type Information Sets if the ABS module receives invalid longitudinal acceleration data from the RCM. This can be due to an incorrectly installed RCM, an RCM that has not been initialized, or an internal failure of the sensor.
    ABS U0452:86 Invalid Data Received From Restraints Control Module: Signal Invalid Sets if the ABS module receives invalid longitudinal acceleration data from the RCM. This can be due to an incorrectly installed RCM, an RCM that has not been initialized, or an internal failure of the sensor.

    Possible Causes 

    • Network communication concern
    • RCM
    • GWM
    • ABS module

    Visual Inspection and Pre-checks 

    • Make sure the vehicle battery state of charge is at least 80%
    • Make sure the vehicle battery voltage is at least 11 VDC

  2. R1 CHECK THE RCM (RESTRAINTS CONTROL MODULE) COMMUNICATION

    • Ignition ON.

    • Using a diagnostic scan tool, carry out the RCM self-test. Only available in the service information

    Does the RCM communicate with the diagnostic scan tool and return DTCs ' 

    Yes  RETRIEVE and RECORD all RCMDTCs. REFER to: Airbag and Seatbelt Pretensioner Supplemental Restraint System (SRS) . . If there are no DTCs in the RCM, GO to  R3.
    No  GO to  R2.

  3. R2 CHECK THE GWM (GATEWAY MODULE A) COMMUNICATION

    • Using a diagnostic scan tool, carry out the GWM self-test. Only available in the service information

    Does the GWM communicate with the diagnostic scan tool and return DTCs ' 

    Yes  RETRIEVE and RECORD all GWMDTCs. REFER to: Controller Area Network (CAN) Module Communications Network .
     
    No  DIAGNOSE the scan tool does not communicate with the GWM. REFER to: Controller Area Network (CAN) Module Communications Network .

  4. R3 RECHECK THE ABS (ANTI-LOCK BRAKE SYSTEM) MODULE FOR THE LOST COMMUNICATION DTC (DIAGNOSTIC TROUBLE CODE)

    • Using a diagnostic scan tool, clear the ABS module Diagnostic Trouble Codes (DTCs). Only available in the service information

    • Ignition OFF.

    • Ignition ON.

    • NOTE: When retrieving DTCs, ignore all historical or continuous memory DTCs.

      Using a diagnostic scan tool, carry out the ABS module self-test. Only available in the service information

    Are any of the DTCs listed in the DTC Fault Trigger Conditions table present and active in the ABS module? 

    Yes  GO to  R4.
    No  The system is operating correctly at this time. The DTC may have been set due to high network traffic or an intermittent fault condition

  5. R4 REVIEW THE ABS (ANTI-LOCK BRAKE SYSTEM) MODULE SELF-TEST FOR VOLTAGE-REALTED DTCS

    • Review the results from the ABS module self-test.

    Is DTC U3003:16 or U3003:17 present? 

    Yes  For DTC U3003:16, GO to Pinpoint Test A  For DTC U3003:17, GO to Pinpoint Test F 
    No  GO to  R5.

  6. R5 CHECK FOR GWM (GATEWAY MODULE A) DTCS

    • Using a diagnostic scan tool, carry out the GWM self-test. Only available in the service information

    Are any DTCs present and active in the GWM ' 

    Yes  RETRIEVE and RECORD all GWMDTCs. REFER to: Controller Area Network (CAN) Module Communications Network .
     
    No  GO to  R6.

  7. R6 CHECK FOR RCM (RESTRAINTS CONTROL MODULE) DTCS

    • Using a diagnostic scan tool, carry out the RCM self-test. Only available in the service information

    Are any DTCs present and active in the RCM ' 

    Yes  RETRIEVE and RECORD all RCMDTCs. REFER to: Airbag and Seatbelt Pretensioner Supplemental Restraint System (SRS) .
     
    No  GO to  R7.

  8. R7 CHECK FOR OTHER CAUSES OF COMMUNICATION NETWORK CONCERN

    • NOTE: If new modules were installed prior to the DTC being set, the module configuration can be incorrectly set during the PMI or the PMI may not have been carried out.

      Check the vehicle service history for recent service actions related to the RCM or the ABS module. If recent service history is found:

      • Verify the correct replacement module was installed. HVBOM may be used to verify correct part fitment.
      • Verify the configuration of replacement module was correct. Re-configure the module using as-built data if prior configuration is suspect.
      • Verify the module was not obtained from a like vehicle and installed into customer vehicle. Return the swapped module to source vehicle and obtain new replacement module.

    • Operate the system and determine if the observable symptom is still present.

    Is the observable symptom still present? 

    Yes  GO to  R8.
    No  The system is operating correctly at this time. The concern may have been due to incorrect parts replacement procedures or incorrect module configuration.

  9. R8 CHECK FOR COMMUNICATION DTCS IN OTHER MODULES

    • Ignition ON.

    • NOTE: When retrieving DTCs, ignore all historical or continuous memory DTCs.

      Using a diagnostic scan tool, carry out a Network Test.

    Is any DTC from the Fault Trigger Conditions Table set in 1 or more modules in addition to the ABS module? 

    Yes  GO to  R9.
    No  GO to  R10

  10. R9 VERIFY RCM (RESTRAINTS CONTROL MODULE) OPERATION

    • Ignition OFF.

    • Disconnect GWM C2451.

    • Disconnect ABS Module C135.

    • Using a good light source, inspect all disconnected electrical connectors for the following:

      • corrosion - install new connector or terminal and clean the module pins
      • damaged or bent pins - install new terminals or pins
      • pushed-out pins - install new pins as necessary
      • spread terminals - install new terminals as necessary

    • Connect RCM C310A Make sure the connector seats and latches correctly.

    • Connect RCM C310B Make sure the connector seats and latches correctly.

    • Connect GWM C2451 Make sure the connector seats and latches correctly.

    • Connect ABS Module C135 Make sure the connector seats and latches correctly.

    • Operate the system and verify the concern is still present.

    Is the concern still present? 

    Yes  CHECK OASIS for any service articles: TSB, GSB, SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new RCM. REFER to: Restraints Control Module (RCM) .
    No  The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.

  11. R10 VERIFY ABS (ANTI-LOCK BRAKE SYSTEM) OPERATION

    • Ignition OFF.

    • Disconnect GWM C2451.

    • Disconnect ABS Module C135.

    • Using a good light source, inspect all disconnected electrical connectors for the following:

      • corrosion - install new connector or terminal and clean the module pins
      • damaged or bent pins - install new terminals or pins
      • pushed-out pins - install new pins as necessary
      • spread terminals - install new terminals as necessary

    • Connect RCM C310A Make sure the connector seats and latches correctly.

    • Connect RCM C310B Make sure the connector seats and latches correctly.

    • Connect GWM C2451 Make sure the connector seats and latches correctly.

    • Connect ABS Module C135 Make sure the connector seats and latches correctly.

    • Operate the system and verify the concern is still present.

    Is the concern still present? 

    Yes  CHECK OASIS for any service articles: TSB, GSB, SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new EBB unit. REFER to: Electric Brake Booster (EBB) .
    No  The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.
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