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Possible Causes

  1. I1: 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 PCM pass the Network Test? 
    Yes No
    Go to  I2. DIAGNOSE the PCM does not communicate with the diagnostic scan tool. REFER to COMMUNICATIONS NETWORK .
  2. I2: RECHECK FOR DTC P1571:64 
    • Carry out the ABS self-test.
    • Clear the ABS DTCs.
    • Ignition OFF.
    • Ignition ON, engine OFF.
    • Carry out the ABS self-test.
    • Record all retrieved ABS module DTCs.
    • Is DTC P1571:64 retrieved again? 
    Yes No
    Go to  I3. If no DTCs are present, the system is operating correctly at this time. The DTC may have been set due to high network traffic or an intermittent fault condition.
    If DTC U0100:xx, U0101:xx, U0104:xx, U0401:xx, U0402:xx or U0405:xx is present, Go to  I5.
  3. I3: INSPECT THE STOPLAMP SWITCH 
    • Inspect the stoplamp switch for correct installation and obvious signs of damage.
    • Observe the stoplamp switch while pressing and releasing the brake pedal.
    • Is the stoplamp switch correctly installed, free from obvious signs of damage and does it operate correctly? 
    Yes No
    Go to  I5. If the switch is damaged, INSTALL a new stoplamp switch. REFER to EXTERIOR LIGHTING (EXCEPT ELECTRIC) .
    If the switch is not installed correctly or does not operate correctly, Go to  I4.
  4. I4: VERIFY BRAKE PEDAL SWITCH INSTALLATION 
    NOTE: Follow all notes and cautions in the stoplamp switch removal and installation procedure.
    • Remove and install the stoplamp switch. Refer to the EXTERIOR LIGHTING (EXCEPT ELECTRIC)
    • Test drive the vehicle at speeds above 20 km/h (12 mph) and carry out at least 2 complete stops.
    • Carry out the ABS self-test.
    • Is DTC P1571:64 retrieved again? 
    Yes No
    Go to  I5. The system is operating correctly at this time. The DTC may have been set due to an incorrectly installed stoplamp switch.
  5. I5: REVIEW THE ABS MODULE SELF-TEST FOR VOLTAGE-RELATED DTCS 
    • Review the recorded DTCs from the ABS 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  I6.
  6. I6: CHECK FOR PCM DTCS 
    • Carry out the PCM KOEO self-test.
    • Are any DTCs present? 
    Yes No
    DIAGNOSE the PCM DTC. REFER to Electronic Engine Controls article Go to  I7.
  7. I7: 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 PCM 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  I8. The system is operating correctly at this time. The concern may have been due to incorrect parts replacement procedures or incorrect module configuration.
  8. I8: CHECK FOR LOST COMMUNICATION DTC SET IN OTHER MODULES 
    • Retrieve the continuous memory DTCs.
    • Is DTC P1571:64, U0100:xx, U0101:xx, U0104:xx, U0401:xx, U0402 or U0405:xx set in 1 or more modules in addition to the ABS module? 
    Yes No
    CHECK OASIS for any applicable Technical Service Bulletins TSBs.
    If a TSB exists for this concern, DISCONTINUE this test and FOLLOW the TSB instructions.
    If no TSBs address this concern, INSTALL a new PCM. REFER to the appropriate Electronic Engine Controls article
    Go to  I9.    		 Go to  I10.
  9. I9: VERIFY PCM OPERATION 
    • Ignition OFF.
    • PCM_B connector disconnected.
    • PCM_E connector disconnected.
    • ABS Module connector disconnected.
    • Disconnect all in-line electrical connectors between the ABS module and the PCM.
    • 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 all in-line electrical connectors between the ABS module and the PCM. Make sure the connectors seat and latch correctly.
    • ABS Module connector connected. Make sure the connector seats and latches correctly.
    • PCM_E connector connected. Make sure the connector seats and latches correctly.
    • PCM_B 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 PCM.
    CHECK OASIS for any applicable Technical Service Bulletins TSBs.
    If a TSB exists for this concern, DISCONTINUE this test and FOLLOW the TSB instructions.
    If no TSBs address this concern, INSTALL a new PCM. REFER to the appropriate Electronic Engine Controls 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.
    If this is a Ford paid repair, INCLUDE the RVC on the warranty claim form.
  10. I10: VERIFY ABS MODULE OPERATION 
    • Ignition OFF.
    • ABS Module connector disconnected.
    • PCM_B connector disconnected.
    • PCM_E connector disconnected.
    • Disconnect all in-line electrical connectors between the ABS module and the PCM.
    • 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 all in-line electrical connectors between the ABS module and the PCM. Make sure the connectors seat and latch correctly.
    • PCM_E connector connected. Make sure the connector seats and latches correctly.
    • PCM_B connector connected. Make sure the connector seats and latches correctly.
    • ABS 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 ABS module.
    CHECK OASIS for any applicable TSBs.
    If a TSB exists for this concern, DISCONTINUE this test and FOLLOW the TSB instructions.
    If no TSBs address this concern, INSTALL a new ABS module. REFER to ANTI-LOCK BRAKE SYSTEM (ABS) MODULE
    ORDER a replacement ABS module 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.
    If this is a Ford paid repair, INCLUDE the RVC on the warranty claim form.
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