Pinpoint Test C: DTC C1222 - Wheel Speed Mismatch, DTC C1237 (REAR), DTC C1233 (LF), DTC C1234 (RF) - Wheel Speed Input Signal Missing: Testing
WARNING: This page is about a different car, the 2005 Ford RV Cutaway, 2005 Ford Econoline, 2005 Ford E450 Super Duty, and 2005 Ford Cutaway. However, it is still accessible from the selected car via links, so may be relevant.
- C1 CHECK FOR ANTI-LOCK BRAKE SYSTEM (ABS) MODULE DTCS
- Connect the diagnostic tool.
- Key in ON position.
Retrieve and record the ABS module DTCs.
- Are any DTCs present?
- Yes : If DTC C1222, C1233, C1234 or C1237 is present, GO to C2.
- No : All other DTCs, GO to the ANTI-LOCK BRAKE SYSTEM (ABS) MODULE DIAGNOSTIC TROUBLE CODE (DTC) INDEX .
- C2 MONITOR THE WHEEL SPEED SENSOR PIDS
- Enter the following diagnostic mode on the diagnostic tool: Anti-Lock Brake System (ABS) PIDs.
- Use the diagnostic tool to monitor the wheel speed sensor PIDs while driving the vehicle at a constant speed.
- Are the wheel speed sensor PID values similar?
- Yes : RETRIEVE the DTCs. If DTC C1233, C1234 or C1237 is present, GO to C5.
- No : GO to C3.
- C3 CHECK THE WHEEL SPEED SENSOR FOR DAMAGE AND/OR LOOSENES
- Key in OFF position.
- Raise and support the vehicle. Refer to IDENTIFICATION CODES .
- Inspect the wheel speed sensor mounting for looseness. If the rear wheel speed sensor is suspected, inspect the sensor for corrosion. If the front wheel speed sensor is suspected, check for corrosion on the front anti-lock brake mounting flange. Clean as necessary.
- Is the wheel speed sensor OK?
CAUTION: Examine the wheel speed sensor wire carefully with a good light. Failure to verify damage in the wheel speed sensor wire can lead to unnecessary installation of a new component.- Yes : GO to C4.
- No : INSTALL a new wheel speed sensor. For the front sensor, REFER to FRONT WHEEL SPEED SENSOR RING . CLEAR the DTCs. TEST the system for normal operation. For the rear sensor, REFER to REAR WHEEL SPEED SENSOR RING . CLEAR the DTCs. TEST the system for normal operation.
- C4 CHECK FOR WHEEL SPEED SENSOR RING DAMAGE
- Remove the wheel speed sensor.
- Inspect the wheel speed sensor rings for damaged or missing teeth.
- Is the wheel speed sensor ring OK?
- Yes : GO to C5.
- No : INSTALL a new wheel speed sensor ring. For the front wheel speed sensor ring, REFER to FRONT WHEEL SPEED SENSOR RING . CLEAR the DTCs. TEST the system for normal operation. For the rear wheel speed sensor ring, REFER to REAR WHEEL SPEED SENSOR RING . CLEAR the DTCs. TEST the system for normal operation.
- C5 CHECK THE SENSOR OUTPUT TO THE ANTI-LOCK BRAKE SYSTEM (ABS) MODULE
- Key in OFF position.
- Disconnect: ABS Module C135.
- Select NEUTRAL.
- Raise and support the vehicle. Refer to IDENTIFICATION CODES .
- Measure the A/C voltage between the ABS module C135, harness side, while spinning the front tire or the driveshaft by hand as follows:ABS MODULE C135 CONNECTOR SPECIFICATIONS
Connector-Pin Circuit Connector-Pin Circuit C135 pin 13 514 (YE/RD) C135 pin 5 516 (YE/BK) C135 pin 12 521 (TN/OG) C135 pin 4 522 (TN/BK) C135 pin 14 523 (RD/BK) C135 pin 6 519 (LG/BK) - Is there an A/C voltage present while the wheel is spinning?
NOTE: For the rear speed sensor, spinning the wheel will not turn the tone ring. You must spin the driveshaft to get accurate test results.- Yes : GO to C8.
- No : GO to C6.
- C6 CHECK THE WHEEL SPEED SENSOR OUTPUT
- Disconnect: Suspect Wheel Speed Sensor.
- Measure the A/C voltage between the suspect wheel speed sensor pins 1 and 2, component side while spinning the front tire or the driveshaft by hand.
- Is the wheel speed sensor output between 300 and 3,500 mVolts?
NOTE: For the rear speed sensor, spinning the wheel will not turn the tone ring. You must spin the driveshaft to get accurate test results.- Yes : GO to C7.
- No : INSTALL a new wheel speed sensor. For the front sensor, REFER to FRONT WHEEL SPEED SENSOR RING . CLEAR the DTC. TEST the system for normal operation. For the rear sensor, REFER to REAR WHEEL SPEED SENSOR RING . CLEAR the DTC. TEST the system for normal operation.
- C7 CHECK THE ANTI-LOCK BRAKE SYSTEM (ABS) CONTROL MODULE OUTPUT
- Key in OFF position.
- Measure the resistance between the ABS module C135 harness side, and the suspect wheel speed sensor connector, harness side as follows:ABS MODULE C135 CONNECTOR SPECIFICATIONS
Connector-Pin Circuit C135 pin 5 516 (YE/BK) C135 pin 13 514 (YE/RD) C135 pin 4 522 (TN/BK) C135 pin 12 521 (TN/OG) C135 pin 14 523 (RD/PK) C135 pin 6 519 (LG/BK) - Are the resistance less than 5 ohms?
- Yes : GO to C8.
- No : REPAIR the circuit(s) in question. TEST the system for normal operation.
- C8 CHECK FOR CORRECT ABS MODULE OPERATION
- Disconnect all ABS connectors.
- Check for:
- corrosion
- pushed-out pins
- Connect all ABS connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
- Yes : INSTALL a new ABS module. REFER to ANTI-LOCK BRAKE SYSTEM (ABS) MODULE . TEST the system for normal operation.
- No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.