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Home >> Ford >> 2018 >> Focus ST >> Repair and Diagnosis >> Brakes >> Brakes Control Systems >> Abs Guided Routine Testing >> Pinpoint Tests >> Pinpoint Test H: HCU Pump Faults >> Possible Causes
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Possible Causes

CAUTION: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may cause damage to the connector.
  1. H1: CHECK THE VEHICLE BATTERY AND CHARGING SYSTEM 
    Yes No
    Go to  H2. FOLLOW the diagnostic repair directions as instructed in CHARGING SYSTEM - GENERAL INFORMATION (EXCEPT ELECTRIC)
  2. H2: VERIFY ALL WIRING CONNECTIONS 
    • 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
    • Is connector free of terminal corrosion, pushed-out terminals and spread terminals? 
    Yes No
    Go to  H3. REPAIR the affected terminal. Refer to OEM CONNECTOR REPAIR PROCEDURES (EXCEPT ELECTRIC) , for schematic and connector information.
  3. H3: CHECK PUMP MOTOR OPERATION 
    • ABS Module connector connected. Make sure the connector seats and latches correctly.
    • Ignition ON, engine OFF.
    • Access the ABS and control the PMP_MTR (MODE) PID.
    • Command the pump motor on and listen for the ABS pump motor to activate.
    • Does the ABS pump motor run for approximately 2 seconds when commanded on? 
    Yes No
    Go to  H4. Go to  H5.
  4. H4: CHECK FOR FAULT REPEATABILITY 
    • Clear the ABS DTCs.
    • Ignition OFF.
    • Ignition ON, engine OFF.
    • Test drive the vehicle at speeds greater than 20 km/h (12 mph).
    • Ignition OFF.
    • Ignition ON, engine OFF.
    • Carry out the ABS self-test.
    • Is DTC C0020:71 or C1B02:71 present? 
    Yes No
    Go to  H7. For all other C0020:xx and C1 B02:xx DTCs, Go to  H5.
    For all other DTCs, No fault found.
    GO to the ABS - ANTILOCK BRAKING SYSTEM DTC INDEX .
    If there are no DTCs present, No fault found the system is operating correctly at this time. DISCONNECT and INSPECT the ABS module electrical connector. CLEAN or REPAIR the connector as necessary. ADDRESS the root cause of any connector or pin issues.
  5. H5: CHECK THE PUMP MOTOR VOLTAGE SUPPLY TO THE ABS MODULE 
    • Ignition OFF.
    • Disconnect the ABS module electrical connector.
    • Measure the voltage between:
      (+) ABS Module Connector, Harness Side (-)
      Motor B+ Ground
    • Is the voltage greater than 11 volts? 
    Yes No
    Go to  H6. REPAIR the circuit.
  6. H6: CHECK THE ABS MODULE GROUND CIRCUIT FOR AN OPEN 
    Yes No
    Go to  H7. REPAIR the circuit.
  7. H7: VERIFY ALL WIRING CONNECTIONS 
    • 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
    • Are the connectors free of corrosion, damaged pins, bent pins, pushed-out pins and spread terminals? 
    Yes No
    Go to  H9. REPAIR the connector or terminals. Refer to OEM CONNECTOR REPAIR PROCEDURES (EXCEPT ELECTRIC) , for schematic and connector information.
  8. H8: CHECK FOR CORRECT HCU OPERATION 
    • ABS Module connector connected. Make sure the connector seats and latches correctly.
    • Connect the battery negative cable. Refer to the General Procedure in CHARGING SYSTEM (BATTERY, MOUNTING AND CABLES) (EXCEPT ELECTRIC) .
    • Operate the system and determine if the concern is still present.
    • Is the concern still present? 
    Yes No
    INSTALL a new HCU.
    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. REFER to REMOVAL AND INSTALLATION
    ORDER a replacement HCU 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.
  9. H9: CHECK FOR CORRECT ABS MODULE AND HCU OPERATION 
    • ABS Module connector connected. Make sure the connector seats and latches correctly.
    • Connect the battery negative cable. Refer to the General Procedure in BATTERY DISCONNECT AND CONNECT .
    • Operate the system and determine if the concern is still present.
    • Is the concern still present? 
    Yes No
    INSTALL a new ABS module.
    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 REMOVAL AND INSTALLATION
    ORDER a replacement ABS module and HCU assembly 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.
  10. H10: CHECK FOR CORRECT ABS MODULE OPERATION 
    • ABS Module connector connected. Make sure the connector seats and latches correctly.
    • Connect the battery negative cable. Refer to the General Procedure in BATTERY DISCONNECT AND CONNECT .
    • Operate the system and determine if the concern is still present.
    • Is the concern still present? 
    Yes No
    INSTALL a new ABS module.
    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 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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