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Home >> Ford >> 2020 >> Edge ST-Line, FWD >> Repair and Diagnosis >> Brakes >> Brakes Control Systems >> Abs Guided Routine >> Pinpoint Tests >> Pinpoint Tests CL: ABS Module Communication Concern With APIM >> Possible Causes
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Possible Causes

  1. CL1: CHECK THE COMMUNICATION NETWORK 
    • 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 APIM pass the Network Test? 
      Yes No
      RETRIEVE and RECORD all APIM DTCs. REFER to the appropriate Information and Entertainment System article. If there are no DTCs in the APIM, Go to  CL2. DIAGNOSE the APIM does not communicate with the diagnostic scan tool. REFER to the Module Communications Network article.
  2. CL2: RECHECK THE ABS MODULE FOR THE LOST COMMUNCATION DTC 
    • Clear the ABS 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, engine OFF.

      Carry out the ABS self-test.

    • Are any of the DTCs listed in the Fault Trigger Conditions table still present? 
      Yes No
      Go to  CL3. The system is operating correctly at this time. The DTC may have been set due to high network traffic or an intermittent fault condition.
  3. CL3: REVIEW THE ABS 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 No
      For DTC U3003:16, GO to PINPOINT TEST A .
      For DTC U3003:17, GO to PINPOINT TEST F .      		 Go to  CL4.
  4. CL4: CHECK FOR APIM DTCS 

    Carry out the APIM self-test.

    • Are any DTCs present? 
      Yes No
      DIAGNOSE the APIM DTC. REFER to the appropriate Information and Entertainment System article. Go to  CL5.
  5. CL5: 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 APIM 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 No
      Go to  CL6. The system is operating correctly at this time. The concern may have been due to incorrect parts replacement procedures or incorrect module configuration.
  6. CL6: CHECK FOR COMMUNICATION DTCS IN OTHER MODULES 
    • Ignition ON, engine OFF.
    • Retrieve the continuous memory DTCs.
    • Is DTC U0253:xx or U0554:xx set in 1 or more modules in addition to the ABS module? 
      Yes No
      Go to  CL7. Go to  CL8.
  7. CL7: VERIFY APIM OPERATION 
    • Ignition OFF.
    • APIM_A connector disconnected.
    • ABS_A Module connector disconnected.
    • ABS_B 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_B Module connector connected. Make sure the connector seats and latches correctly.
    • ABS_A Module connector connected. Make sure the connector seats and latches correctly.
    • APIM_A connector connected. 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
      INSTALL a new APIM.
      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 APIM. REFER to the appropriate Information and Entertainment System article.
      ORDER a replacement APIM and INCLUDE the RVC on the form.
      If this is a Ford paid repair, INCLUDE the RVC on the warranty claim form.      		 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.
  8. CL8: VERIFY ABS OPERATION 
    • Ignition OFF.
    • ABS_A Module connector disconnected.
    • ABS_B Module connector disconnected.
    • APIM_A 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
    • APIM_A connector connected. Make sure the connector seats and latches correctly.
    • ABS_B Module connector connected. Make sure the connector seats and latches correctly.
    • ABS_A Module connector connected. 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
      INSTALL a new EBB assembly.
      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 HCU and ABS module assembly. REFER to the Anti-Lock Brake System (ABS) and Stability Control article.
      ORDER a replacement HCU and ABS module assembly. INCLUDE the RVC on the form.
      If this is a Ford paid repair, INCLUDE the RVC on the warranty claim form.      		 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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