C1235 - FAULT CODE - OBD2

C1235 FORD, LINCOLN, MAZDA, MERCURY: RIGHT REAR WHEEL SPEED SENSOR INPUT SIGNAL MISSING

The ABS Module (Anti-lock Brake System Module) receives readings indicating wheel speed and this information is sent by each Wheel Speed Sensor. With this data, the module can determine if ABS functions need to be performed. If the module detects impending wheel lockup, it regulates the braking pressure to the appropriate brake caliper

A Wheel Speed Sensor has the function of detecting the magnetic field of the sensor ring as it passes over the sensor face while in operation. The sensor circuit is connected to the ABS Module via two wires and a connector for each sensor. When the ignition is placed in the RUN position, the ABS Module performs a series of self-tests by sending a reference voltage to all sensors through its circuitry to determine if they are functioning properly.

C1235 OBD2 diagnostic code is set on Ford, Lincoln, Mazda, and Mercury vehicles when the Right Rear Wheel Speed Sensor input signal is detected to be missing.

• Check Engine light illuminated.
• The light indicating ABS and Traction Control System problems illuminates.
• Various ABS functions cannot be performed.

DTC C1235 OBDII is set by the following:

• One of the tires could be inconsistently sized.
• Right Rear Wheel Speed Sensor wires or connections could be in poor condition.
• The Right Rear Wheel Speed Sensor ring could have been damaged.
• The Right Rear Wheel Speed Sensor may be defective.
• The Anti-Lock Brake System Module could have deficiencies.

In order to troubleshoot the C1235 OBDII fault code you must do the following:

• Consult the Technical Service Bulletins. The manufacturer uses these bulletins to provide help for known problems.
• Through an automotive scanner verify if additional DTCs to C1235 are stored, which are related to ABS. Diagnose the codes in the order obtained.
• Check for deficiencies in the Right Rear Wheel Speed Sensor circuit wiring, connectors, or connections. If common deficiencies are discovered, make appropriate repairs or changes.
• Take into account the manufacturer's recommendations for diagnosing the Right Rear Wheel Speed Sensor ring and the sensor in question. If you detect damage to one of these after testing, proceed with the appropriate adjustments.