Possible Causes

• Fuses
• Wiring, terminals or connectors
• HCU
• ABS module

• Fuses
• Wiring, terminals or connectors
• EBB unit (HCU and ABS module assembly)

Visual Inspection and Diagnostic Pre-checks 

• Make sure the vehicle battery terminals and cables are free of any corrosion and other contaminants.
• Make sure the vehicle battery terminals are tightened to their correct torque specifications.
• Make sure BJB fuse 29 (60A) and the fuse socket are OK.

1. H1: CHECK THE VEHICLE BATTERY AND CHARGING SYSTEM 
   • Verify the vehicle battery and charging system are operating correctly. Refer to Inspection and Verification in Charging System General Information, Diagnosis and Testing.
   • Are the battery and charging system operating correctly? 

     Yes	No
     Go to  H2.	FOLLOW the diagnostic repair directions as instructed in Charging System General Information Diagnosis and Testing.

2. H2: VERIFY ALL WIRING CONNECTIONS 
3. H3: CHECK PUMP MOTOR OPERATION 
4. H4: CHECK FOR FAULT REPEATABILITY 
5. H5: CHECK THE ABS MODULE GROUND CIRCUIT FOR AN OPEN 
6. H6: VERIFY ABS MODULE GROUND CONNECTIONS 
   NOTE: Refer to the Grounds wiring diagrams for ground connection information.
   • Disconnect all ABS module ground joint connections. Refer to the Grounds wiring diagrams for ground information.
     • Discard the bolts.
   • Inspect the ground joint connections for:
     • Rust
     • Corrosion
     • Other foreign material
     • Cross-threaded fasteners
     NOTE: Do not remove any paint from the body as the ground path conduction is through the bolt threads.
   • Clean or repair the ground joint connections as necessary.
   • Connect all ABS module ground joint connections. Make sure the connections are clean, tight and not cross threaded.
     • Install new bolts and tighten to 12 Nm (106 lb-in).
   • Measure the resistance between:
     • Each ground joint bolt.
     • The battery negative cable terminal.
   • Are the measured resistances less than 1 Ohm? 

     Yes	No
     Go to  H7.	CLEAN or REPAIR the ground joint connection. Go to  H7.

7. H7: CHECK THE PUMP MOTOR VOLTAGE SUPPLY TO THE ABS MODULE 
   NOTE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may cause damage to the connector.
   NOTE: This step puts a load on the ABS module voltage supply circuit. If there are corroded or loose connections, loading the circuit may help show the fault. A 9006 or 9007 headlamp bulb is an effective load.
   NOTE: VERIFY BJB fuse 29 (60A) is OK. If not OK, REFER to the OEM Electrical Wiring Diagrams Introduction article to identify the possible causes of the circuit short.
   • Ignition ON, engine OFF.
   • Measure the voltage between:

     (+) Vehicle Battery	(-) Vehicle Battery
     Positive terminal	Negative terminal

   • Record the measured battery voltage.
   • Connect the load to a suitable ground connection.
   • Connect the load to each circuit before taking the voltage measurement.
   • Measure the voltage between:

     (+) ABS Module (C155) Connector, Harness Side	(-)
     Motor B+ - SBB29 (GRAY/RED) - Pin 1	Ground

   • Measure the voltage between:

     (+) ABS_B Module (C135B) Connector, Harness Side	(-)
     PUMPPWR	Ground

   • Measure the voltage between:

     (+) ABS_A Module (C135A) Connector, Component Side	(-)
     VLVPWR	Ground

   • Is each voltage within 0.5 volt of the recorded battery voltage? 

     Yes	No
     Go to  H8.	REPAIR the circuit.

8. H8: VERIFY ALL WIRING CONNECTIONS 
   • 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? 
9. H9: CHECK FOR APPLICABLE SERVICE ARTICLES 
   • Check OASIS for any service articles: TSB, GSB, SSM or FSA.
   • Do any applicable service articles exist? 
10. H10: CHECK FOR CORRECT ABS MODULE AND HCU OPERATION 
    • ABS Module connector connected. (C155) Make sure the connector seats and latches correctly.
    • Operate the system and determine if the concern is still present.
    • Is the concern still present? 

      Yes	No
      INSTALL a new HCU. 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 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.

11. H11: CHECK FOR CORRECT ABS OPERATION 
    • ABS_A Module connector connected. (C135A) Make sure the connector seats and latches correctly.
    • ABS_B Module connector connected. (C135B) Make sure the connector seats and latches correctly.
    • Operate the system and determine if the concern is still present.
    • Is the concern still present? 

      Yes	No
      INSTALL a new EBB assembly. The HCU and ABS module are a single assembly known as the EBB unit. INSTALL a new EBB unit (HCU and ABS module assembly). REFER to the Anti-Lock Brake System (ABS) and Stability Control article. ORDER a replacement EBB unit 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.