Pinpoint Test Am: DTC U0129 - Lost Communication With Brake System Control Module

2010 Mercury Mariner Hybrid, AWDSECTION Pinpoint Test Am: DTC U0129 - Lost Communication With Brake System Control Module
WARNING: This page is about a different car, the 2008 Mercury Mariner and 2008 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
  1. AM1 RETRIEVE THE RECORDED DTCs FROM BOTH THE CONTINUOUS AND ON-DEMAND INSTRUMENT CLUSTER (IC) SELF-TESTS 
    • Check for recorded instrument cluster (IC) DTCs from the continuous and on-demand self-tests.
    • Is DTC B1318 recorded? 
    1. YES  : Go to Pinpoint Test AG .
    2. NO  : Go to  AM2.
  2. AM2 RECHECK THE INSTRUMENT CLUSTER (IC) DTCs 
    • Clear the DTCs.
    • Repeat the instrument cluster (IC) self-test.
    • Is DTC U0129 still present? 
    1. YES  : Go to  AM3.
    2. NO  : The system is operating correctly at this time. The DTC may have been set due to high network traffic.
  3. AM3 CHECK THE PCM FOR DTC U0129 
    • Carry out the self-test on the PCM.
    • Is DTC U0129 retrieved? 
    1. YES  : REFER to MODULE COMMUNICATIONS NETWORK article to diagnose no communication with the ABS module.
    2. NO  : Go to  AM4.
  4. AM4 CHECK FOR CORRECT INSTRUMENT CLUSTER (IC) OPERATION 
    • Disconnect the instrument cluster (IC) connector.
    • Check for:
      • corrosion
      • damaged pins
      • pushed-out pins
    • Connect the instrument cluster (IC) connector and make sure it seats correctly.
    • Operate the system and verify the concern is still present.
    • Is the concern still present? 
    1. YES  : INSTALL a new instrument cluster (IC). REFER to Instrument Cluster (IC) . TEST the system for normal operation.
    2. NO  : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
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