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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
Fig 1: Antilock Braking System (ABS) Module Connector - C135
GFDWR118226Courtesy of FORD MOTOR COMPANY

Harness Side

Circuit Pin
Fig 2: Left Front Wheel Speed Sensor Connector - C150
G13419140Courtesy of FORD MOTOR CO.

Harness Side

Circuit Pin
LF WSS HI (Left Front Wheel Speed Sensor High) - VCA03 1 (VIOLET/WHITE)
LF WSS LO (Left Front Wheel Speed Sensor Low) - RCA17 2 (YELLOW)
Fig 3: Right Front Wheel Speed Sensor Connector - C160
G13419141Courtesy of FORD MOTOR CO.

Harness Side

Circuit Pin
RF WSS HI (Right Front Wheel Speed Sensor HI) - VCA05 1 (GRAY/VIOLET)
RF WSS LO (Right Front Wheel Speed Sensor Low) - RCA19 2 (VIOLET)
Fig 4: Left Rear Wheel Speed Sensor Connector - C440
G13419142Courtesy of FORD MOTOR CO.

Harness Side

Circuit Pin
LR WSS HI (Left Rear Wheel Speed Sensor High) - VCA04 1 (BLUE/ORANGE)
LR WSS LO (Left Rear Wheel Speed Sensor Low) - RCA18 2 (BROWN/GREEN)
Fig 5: Right Rear Wheel Speed Sensor Connector - C426
G13419143Courtesy of FORD MOTOR CO.

Harness Side

Circuit Pin
RR WSS HI (Right Rear Wheel Speed Sensor High) - VCA06 1 (WHITE/ORANGE)
RR WSS LO (Right Rear Wheel Speed Sensor Low) - RCA20 2 (BROWN)
  1. AB1: CHECK FOR ABS MODULE DTCS 
    • Ignition ON, engine OFF.

      Carry out the ABS self-test.

    • Is DTC C003x:29 or C003x:64 present? 
      Yes No
      Go to  AB2. For DTC C0031:07, C0034:07, C0037:07, C003A:07, C0031:2F, C0034:2F, C0037:2F or C003A:2F, Go to  AB3.
      For DTC C0030:07, C0033:07, C0036:07 or C0039:07, Go to  AB6.
  2. AB2: CHECK THE TIRES SIZE AND PRESSURE 
    • Ignition OFF.
    • Verify all the tires and wheels are the same size and the tire size and inflation pressures are correct as indicated on the VC label.
    • Are the tires and wheels OK? 
      Yes No
      Go to  AB3. INSTALL the correct size tire or wheel or ADJUST tire pressure as necessary.
      DRIVE the vehicle at a speed greater than 20 km/h (12 mph) to clear the ABS module wheel speed sensor DTCs.
  3. AB3: CHECK THE WHEEL SPEED SENSOR MOUNTING 
    • With the transmission in NEUTRAL, position the vehicle on a hoist. Refer to the Jacking and Lifting article.
    • Inspect the wheel speed sensor for correct installation and the fastener for looseness.
    • Is the wheel speed sensor installed correctly and the fastener tightened to specifications? 
      Yes No
      Go to  AB5. REINSTALL the wheel speed sensor and tighten the fastener to specifications. REFER to the appropriate procedure in the Anti-Lock Brake System (ABS) and Stability Control article. Go to  AB4.
  4. AB4: CHECK THE WHEEL SPEED SENSOR INPUTS 
    • Ignition ON, engine OFF.
    • Access the ABS and monitor the LF_WSPD (SPD) PID.
    • Access the ABS and monitor the RF_WSPD (SPD) PID.
    • Access the ABS and monitor the LR_WSPD (SPD) PID.
    • Access the ABS and monitor the RR_WSPD (SPD) PID.
    • Drive the vehicle at a speed greater than 20 km/h (12 mph) while monitoring the PIDs.
    • Are the wheel speed PIDs within 5 km/h (3 mph) of each other and the vehicle speed as indicated on the speedometer? 
      Yes No
      The system is operating correctly at this time. The concern may have been caused by a loose or incorrectly installed wheel speed sensor. DRIVE the vehicle at a speed greater than 20 km/h (12 mph) to clear the ABS module wheel speed sensor DTCs. Go to  AB5.
  5. AB5: CHECK THE WHEEL SPEED SENSOR FOR DAMAGE 
    • Ignition OFF.
    • With the transmission in NEUTRAL, position the vehicle on a hoist. Refer to the Jacking and Lifting article.
    • Disconnect the suspect wheel speed sensor electrical connector.
    • Inspect the wheel speed sensor and harness for abrasions, broken connector tabs or water intrusion.
    • Are the wheel speed sensor and harness OK? 
      Yes No
      Go to  AB6. INSTALL a new WSS.
      REFER to the Anti-Lock Brake System (ABS) and Stability Control article.
      DRIVE the vehicle at a speed greater than 20 km/h (12 mph) to clear the ABS module wheel speed sensor DTCs.
  6. AB6: CHECK WHEEL BEARING AND ENCODER FOR DAMAGE 
    • Ignition OFF.
    • With the transmission in NEUTRAL, position the vehicle on a hoist. Refer to the Jacking and Lifting article.
    • Inspect the wheel bearings for abnormal wear or roughness and for deformation or contamination of the seal and encoder.
    • Are the wheel bearing and encoder OK? 
      Yes No
      Go to  AB8. INSTALL a new wheel bearing as necessary. REFER to the appropriate Service Information.
      DRIVE the vehicle at a speed greater than 20 km/h (12 mph) to clear the ABS module wheel speed sensor DTCs.
  7. AB7: CHECK THE WHEEL SPEED SENSOR PIDS 
    • Ignition ON, engine OFF.
    • Access the ABS and monitor the LF_WSPD (SPD) PID.
    • Access the ABS and monitor the RF_WSPD (SPD) PID.
    • Access the ABS and monitor the LR_WSPD (SPD) PID.
    • Access the ABS and monitor the RR_WSPD (SPD) PID.
    • Drive the vehicle at a speed greater than 48 km/h (30 mph) while monitoring the PIDs.
    • Are the wheel speed PIDs within 5 km/h (3 mph) of each other and the vehicle speed as indicated on the speedometer? 
      Yes No
      Go to  AB8. CLEAN the space between the wheel speed sensor encoder ring and the wheel speed sensor. INSPECT the air gap. INSTALL a new wheel bearing or wheel speed sensor as necessary. REFER to the Front Suspenstion article, Rear Suspension article or the Anti-Lock Brake System (ABS) and Stability Control article.
      DRIVE the vehicle at a speed greater than 20 km/h (12 mph) to clear the ABS module wheel speed sensor DTCs.
  8. AB8: CHECK FOR CORRECT ABS MODULE OUTPUT 
    • Ignition OFF.
    • Disconnect the suspect wheel speed sensor electrical connector.
    • Ignition ON, engine OFF.
    • Measure the voltage between:
      (+) Left Front Wheel Speed Sensor Sensor (C150) Connector, Harness Side (-) Left Front Wheel Speed Sensor Sensor (C150) Connector, Harness Side
      LF WSS HI - VCA03 (VIOLET/WHITE) - Pin 1 LF WSS LO - RCA17 - Pin 2
    • Measure the voltage between:
      (+) Right Front Wheel Speed Sensor (C160) Connector, Harness Side (-) Right Front Wheel Speed Sensor (C160) Connector, Harness Side
      RF WSS HI - VCA05 (GRAY/VIOLET) - Pin 1 RF WSS LO - RCA19 - Pin 2
    • Measure the voltage between:
      (+) Left Rear Wheel Speed Sensor (C440) Connector, Harness Side (-) Left Rear Wheel Speed Sensor (C440) Connector, Harness Side
      LR WSS HI - VCA04 (BLUE/ORANGE) - Pin 1 LR WSS LO - RCA18 - Pin 2
    • Measure the voltage between:
      (+) Right Rear Wheel Speed Sensor (C426) Connector, Harness Side (-) Right Rear Wheel Speed Sensor (C426) Connector, Harness Side
      RR WSS HI - VCA06 (WHITE/ORANGE) - Pin 1 RR WSS LO - RCA20 - Pin 2
    • Is the voltage greater than 10 volts? 
      Yes No
      INSTALL a new WSS.
      REFER to the Anti-Lock Brake System (ABS) and Stability Control article.
      DRIVE the vehicle at a speed greater than 20 km/h (12 mph) to clear the ABS module wheel speed sensor DTCs.      		 Go to  AB9.
  9. AB9: VERIFY ALL WIRING CONNECTIONS 
    • Ignition OFF.
      NOTE: The battery must be removed to access the ABS module electrical connector.
    • Remove the battery. Refer to the appropriate procedure in the Battery, Mounting and Cables article.
    • ABS Module connector disconnected. (C135)
    • Disconnect the suspect wheel speed electrical connector.
    • 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  AB10. REPAIR the connector or terminals. Refer to the Connector Repair Procedures wiring diagrams for schematic and connector information.
      DRIVE the vehicle at a speed greater than 20 km/h (12 mph) to clear the ABS module wheel speed sensor DTCs.
  10. AB10: CHECK FOR APPLICABLE SERVICE ARTICLES 
    • Check OASIS for any service articles: TSB, GSB, SSM or FSA.
    • Do any applicable service articles exist? 
  11. AB11: CHECK FOR CORRECT ABS MODULE OPERATION 
    • Connect the suspect wheel speed sensor. Make sure it seats and latches correctly.
    • ABS Module connector connected. (C135) Make sure the connector seats and latches correctly.
    • Install the battery. Refer to the appropriate procedure in the Battery, Mounting and Cables article.
    • Operate the system and determine if the concern is still present.
    • Is the concern still present? 
      Yes No
      INSTALL a new ABS module.
      INSTALL a new ABS module. REFER to the Anti-Lock Brake System (ABS) and Stability Control article.
      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.
      DRIVE the vehicle at a speed greater than 20 km/h (12 mph) to clear the ABS module wheel speed sensor DTCs.      		 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.
      DRIVE the vehicle at a speed greater than 20 km/h (12 mph) to clear the ABS module wheel speed sensor DTCs.
  12. AB12: CHECK FOR CORRECT ABS OPERATION 
    • Connect the suspect wheel speed sensor. Make sure it seats and latches correctly.
    • ABS_A Module connector connected. Make sure the connector seats and latches correctly.
    • ABS_B Module connector connected. 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 unit known as the EBB assembly.
      INSTALL a new EBB assembly
      (HCU and ABS module). REFER to the Anti-Lock Brake System (ABS) and Stability Control article.
      ORDER a replacement EBB assembly and INCLUDE the RVC form.
      If this is a Ford paid repair, INCLUDE the RVC on the warranty claim form.
      DRIVE the vehicle at a speed greater than 20 km/h (12 mph) to clear the ABS module wheel speed sensor DTCs.      		 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.
      DRIVE the vehicle at a speed greater than 20 km/h (12 mph) to clear the ABS module wheel speed sensor DTCs.
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