Pinpoint Test F: DTC C1233, DTC C1234, DTC C1235, DTC C1236 - Wheel Speed Sensor Input Signal Missing
WARNING: This page is about a different car, the 2005 Mercury Mountaineer and 2005 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION:
Use the flex probe kit for all test connections to prevent damage to the wiring terminals. Do not use standard multimeter probes.
NOTE:
Vehicles without traction control and stability assist have a single rear wheel speed sensor mounted to the rear differential. DTCs C1235 or C1236 sets if there is a rear wheel speed sensor input signal missing; C1235 can be disregarded.
- F1 CHECK THE DTCs FROM THE SELF-TEST
- Check the recorded results from the anti-lock brake system (ABS) self-test.
- Are DTCs C1145, C1155, C1165, or C1175 present?
- Yes : GO to PINPOINT TEST E .
- No : GO to F2.
- F2 MONITOR THE WHEEL SPEED PIDS
- Connect the diagnostic tool.
- Key in ON position.
- Enter the following diagnostic mode on the diagnostic tool: ABS Module PIDs.
- Use the diagnostic tool to monitor the ABS module wheel speed sensor PIDs while driving the vehicle at a constant speed.
- Are all the wheel speed sensor PID values similar?
- Yes : CLEAR the DTCs. DRIVE the vehicle. RETRIEVE the DTCs. If DTC C1233, C1234, C1235, or C1236 is present, GO to F9.
- No : GO to F3.
- F3 INSPECT THE WHEEL SPEED SENSOR MOUNTING
- Key in OFF position.
- With the vehicle in NEUTRAL, position it on a hoist. Refer to JACKING AND LIFTING .
- Inspect the wheel speed sensor for looseness.
- Is the wheel speed sensor loose?
- Yes : TIGHTEN the wheel speed sensor to specification. CLEAR the DTCs. GO to F4.
- No : GO to F5.
- F4 RECHECK THE WHEEL SPEED PIDS
- Connect the diagnostic tool.
- Key in ON position.
- Enter the following diagnostic mode on the diagnostic tool: ABS Module PIDs.
- Use the diagnostic tool to monitor the ABS module wheel speed sensor PIDs while driving the vehicle at a constant speed.
- Are all the wheel speed sensor PID values similar?
- Yes : The vehicle is OK. The concern may have been caused by a loose wheel speed sensor.
- No : GO to F5.
- F5 CHECK THE WHEEL SPEED SENSOR FOR DAMAGE
- Key in OFF position.
- With the vehicle in NEUTRAL, position it on a hoist. Refer to JACKING AND LIFTING .
- Inspect the wheel speed sensor for general damage.
- Is the wheel speed sensor OK?
CAUTION: Examine the wheel speed sensor wire carefully with a good light source. Failure to verify damage in the wheel speed sensor wire can lead to unnecessary installation of a new component.- Yes : GO to F6.
- No : INSTALL a new wheel speed sensor. REFER to WHEEL SPEED SENSOR - FRONT , WHEEL SPEED SENSOR - REAR, 3 CHANNEL or WHEEL SPEED SENSOR - REAR, 4 CHANNEL . CLEAR the DTCs. REPEAT the self-test.
- F6 CHECK FOR WHEEL SPEED SENSOR RING DAMAGE
- Inspect the wheel speed sensor ring for damaged or missing teeth. Rotate the wheel to verify that no teeth are missing.
- Is the wheel speed sensor ring OK?
- Yes : GO to F7.
- No : INSTALL a new hub and bearing (front wheel), ring gear (3-channel), or rear halfshaft (4-channel). REFER to FRONT SUSPENSION - 4X2 , FRONT SUSPENSION - 4X4 , REAR DRIVE AXLE/DIFFERENTIAL - FORD 8.8-INCH RING GEAR , or REAR SUSPENSION respectively. CLEAR the DTCs. REPEAT the self-test.
- F7 CHECK FOR BEARING DAMAGE
- Inspect the wheel bearings for damage.
- Are the wheel bearings OK?
- Yes : GO to F8.
- No : INSTALL a new wheel bearing as necessary. REFER to FRONT SUSPENSION - 4X2 or to FRONT SUSPENSION - 4X4 . CLEAR the DTCs. REPEAT the self-test.
- F8 CHECK THE ABS MODULE OUTPUT
- Key in OFF position.
- Disconnect: Suspect Wheel Speed Sensor.
- Key in ON position.
- Measure the voltage between the suspect wheel speed sensor pins, harness side.
- Is the voltage greater than 10 volts?
- Yes : INSTALL a new wheel speed sensor. REFER to WHEEL SPEED SENSOR - FRONT , WHEEL SPEED SENSOR - REAR, 3 CHANNEL or WHEEL SPEED SENSOR - REAR, 4 CHANNEL . CLEAR the DTCs. REPEAT the self-test.
- No : GO to F9.
- F9 CHECK FOR CORRECT ABS MODULE OPERATION
- Disconnect all the ABS connectors.
- Check for:
- corrosion
- pushed-out pins
- Connect all the 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.