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Pinpoint Test Ag: Abs (Anti-Lock Brake System) Module Communication Concern With The GSM (Gear Shift Module)

  1. Refer to Vehicle Dynamic Systems for schematic and connector information.

    Normal Operation and Fault Conditions 

    With the ignition ON, the GWM sends messages to the GSM 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 the specified time frame, the ABS module sets Diagnostic Trouble Codes (DTCs). This can be due to a GSM failure, a circuit failure on the CAN or an excessive load on the network. For information on the messages sent to the ABS module by the GSM.

    For information on the messages sent to the ABS module by the GSM, REFER to: Anti-Lock Brake System (ABS) and Stability Control - Diesel/Flex Fuel - Ethanol/Full Hybrid Electric Vehicle (FHEV)/Gasoline - System Operation and Component Description .

    DTC Fault Trigger Conditions 

    DTC Description Fault Trigger Condition
    ABS U0103:00 Lost Communication With Gear Shift Control Module A: No Sub Type Information This DTC sets when the ABS module does not receive any messages from the GSM within the allowed time.

    Possible Causes 

    • Wiring, terminals or connectors
    • Network communication concern
    • GSM
    • ABS module

  2. AG1 CHECK THE COMMUNICATION NETWORK

    • Ignition ON.

    • Using a diagnostic scan tool, retrieve the DTC s from all modules.

    Does the GSM pass the Network Test? 

    Yes  DIAGNOSE the GSM Diagnostic Trouble Codes (DTCs). If there are no GSM Diagnostic Trouble Codes (DTCs), GO to  AG2
    No  DIAGNOSE the no communication with the GSM. REFER to: Controller Area Network (CAN) Module Communications Network - Electric .

  3. AG2 CHECK FOR RETURNING ABS (ANTI-LOCK BRAKE SYSTEM) MODULE DIAGNOSTIC TROUBLE CODES (DTCS)

    • Using a diagnostic scan tool, clear the ABS module Diagnostic Trouble Codes (DTCs).

    • Put the ABS module in sleep mode by performing the following steps:

      • With ALL doors closed, set the ignition from ON to OFF.
      • Disconnect the diagnostic scan tool.
      • Open the door, exit the vehicle and close the door.
      • Wait a minimum of 90 seconds for the ABS module to enter sleep mode.

    • Ignition ON.

    • Using a diagnostic scan tool, carry out the ABS module self-test.

    Are any of the Diagnostic Trouble Codes (DTCs) in the DTC Fault Trigger Conditions table retrieved again? 

    Yes  GO to  AG3
    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.

  4. AG3 CHECK FOR VOLTAGE-RELATED DIAGNOSTIC TROUBLE CODES (DTCS) IN THE ABS (ANTI-LOCK BRAKE SYSTEM) MODULE

    • Review the recorded Diagnostic Trouble Codes (DTCs) from the ABS module.

    Is DTC U3003:16 or U3003:17 present in the ABS module? 

    Yes  For ABS module DTC U3003:16, GO to Pinpoint Test A  For ABS module DTC U3003:17, GO to Pinpoint Test F 
    No  GO to  AG4

  5. AG4 RETRIEVE ALL GSM (GEAR SHIFT MODULE) DIAGNOSTIC TROUBLE CODES (DTCS)

    • Ignition ON.

    • Using a diagnostic scan tool, carry out the GSM self-test.

    Are any GSM Diagnostic Trouble Codes (DTCs) present? 

    Yes  DIAGNOSE the GSM Diagnostic Trouble Codes (DTCs). REFER to: External Controls - Vehicles With: Column Shift 10R80 . REFER to: External Controls - Vehicles With: Console Shift 10R80 . REFER to: External Controls - Vehicles With: Column Shift 10R80 MHT . REFER to: External Controls - Vehicles With: Console Shift 10R80 MHT .
    No  GO to  AG5

  6. AG5 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 TCCM or 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  AG6
    No  The system is operating correctly at this time. The concern may have been due to incorrect parts replacement procedures or incorrect module configuration.

  7. AG6 CHECK FOR COMMUNICATION DIAGNOSTIC TROUBLE CODES (DTCS) IN OTHER MODULES

    • Ignition ON.

    • Using a diagnostic scan tool, clear the ABS module Diagnostic Trouble Codes (DTCs).

    • Using a diagnostic scan tool retrieve all Diagnostic Trouble Codes (DTCs).

    Is DTC U0103:xx or U0404:xx present in one or more modules in addition to the ABS module? 

    Yes  GO to  AG7
    No  GO to  AG8

  8. AG7 CHECK FOR CORRECT GSM (GEAR SHIFT MODULE) MODULE OPERATION

    • Ignition OFF.

    • Disconnect GSM C2503 (column shift) or C3245 (floor shifter).

    • 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 ABS module C135. Make sure it seats and latches correctly.

    • Connect GSM connector C2503 (column shift) or C3245 (floor shifter). Make sure the connector seats and latches correctly.

    • Operate the system and determine if 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 GSM. REFER to: Gear Shift Module (GSM) - Vehicles With: Column Shift . REFER to: Gear Shift Module (GSM) - Vehicles With: Console Shift .
    No  The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues. Refer to Connector Repair Procedures for schematic and connector information.

  9. AG8 CHECK FOR CORRECT ABS (ANTI-LOCK BRAKE SYSTEM) MODULE OPERATION

    • Ignition OFF.

    • 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 ABS module C135. Make sure it seats and latches correctly.

    • Operate the system and determine if 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 module. 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. Refer to Connector Repair Procedures for schematic and connector information.
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