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Home >> Ford >> 2021 >> Edge ST >> Repair and Diagnosis >> Brakes >> Brakes Control Systems >> Abs Guided Routine - Pinpoint Tests A - AZ >> Pinpoint Tests AU: Abs Module Communication Concern With The TCCM >> Possible Causes
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Possible Causes

  1. AU1: Check The TCCM Communication 
    NOTE: The TCCM may also be known as the AWD module or the 4WD module.
    • Ignition ON, engine OFF.
    • Press the Read Vehicle Information button to view the results of the modules communicating on the network.
    • Retrieve the continuous memory DTCs.
    • Does the TCCM pass the network test? 
    Yes No
    RETRIEVE and RECORD all TCCM DTCs. REFER to the Power Transfer Unit article. If there are no DTCs in the TCCM, Go to  AU3. Go to  AU2.
  2. AU2: Check The Communication To The GWM 
    • Review the results of the modules communicating on the network from the previous step.
    • Did the GWM pass the network test? 
    Yes No
    DIAGNOSE the TCCM does not communicate with the diagnostic scan tool. REFER to the Module Communications Network article. DIAGNOSE the GWM does not communicate with the diagnostic scan tool. REFER to the Module Communications Network article.
  3. AU3: Recheck For The ABS Module DTCs 
    • Clear the ABS DTCs.
    • Ignition ON, engine OFF.

      Carry out the ABS self-test.

    • Record all ABS module DTCs.
    • Are any of the DTCs listed in the Fault Trigger Conditions table retrieved again? 
    Yes No
    Go to  AU4. 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. AU4: Check For Voltage DTCs In The ABS Module 
    • Review the recorded DTCs from the ABS module self-test.
    • Is DTC U3003:16 or U3003:17 present? 
    Yes No
    For DTC U3003:17, GO to Pinpoint Test F.
    For DTC U3003:16, GO to Pinpoint Test A.     		 Go to  AU5.
  5. AU5: Check For DTCs In The GWM 

    Carry out the GWM self-test.

    • Record all DTCs from the GWM self-test.
    • Are any DTCs present? 
    Yes No
    DIAGNOSE the GWM DTCs. REFER to the Module Communications Network article. Go to  AU6.
  6. AU6: Check For DTCs In The TCCM 
    NOTE: The TCCM may also be known as the AWD module or the 4WD module.

    Carry out the TCCM self-test.

    • Record all DTCs from the TCCM self-test.
    • Are any DTCs present? 
    Yes No
    DIAGNOSE the TCCM DTCs. REFER to the appropriate Diagnosis and Testing in the Power Transfer Unit article. Go to  AU7.
  7. AU7: 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 No
    Go to  AU8. The system is operating correctly at this time. The concern may have been due to incorrect parts replacement procedures or incorrect module configuration.
  8. AU8: Check For Communication DTCs In Other Modules 
    • Ignition ON, engine OFF.
    • Clear the ABS DTCs.
    • Retrieve the continuous memory DTCs.
    • Is DTC U0102:xx or U0403:xx set in 1 or more modules in addition to the ABS module? 
  9. AU9: Verify TCCM Operation 
    NOTE: The TCCM may also be known as the AWD module or the 4WD module.
    • Ignition OFF.
    • GWM connector disconnected. (C2431)
    • 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
    • GWM connector connected. (C2431) Make sure the connector seats and latches correctly.
    • Operate the system and verify the concern is still present.
    • Is the concern still present? 
    Yes No
    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 TCCM. REFER to the Power Transfer Unit article.    		 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.
  10. AU10: VERIFY ABS MODULE OPERATION 
    NOTE: The TCCM may also be known as the AWD module or the 4WD module.
    • Ignition OFF.
    • ABS Module connector disconnected.
    • 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
    • ABS Module connector disconnected. Make sure the connector seats and latches correctly.
    • Operate the system and verify the concern is still present.
    • Is the concern still present? 
    Yes No
    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 services articles address this concern, INSTALL a new ABS module. REFER to the Anti-Lock Brake System (ABS) and Stability Control article.    		 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. AU11: Verify ABS Operation 
    NOTE: The TCCM may also be known as the AWD module or the 4WD module.
    • Ignition OFF.
    • 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
    • Operate the system and verify the concern is still present.
    • Is the concern still present? 
    Yes No
    The HCU and ABS module are a single assembly known as the EBB unit.
    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 the Anti-Lock Brake System (ABS) and Stability Control article.    		 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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