C1040 Code: Meaning, Causes, and Symptoms | OBD2 Codes

C1040 – Rear Wheel Speed Comparative Performance


C1040 Possible Symptoms


Anti-Lock Brake System (ABS) Warning Light ON,Engine Light ON (or Service Engine Soon Warning Light)


C1040 Possible Causes


Faulty Rear Wheel Speed Sensor,Rear Wheel Speed Sensor harness is open or shorted,Rear Wheel Speed Sensor circuit poor electrical connection


C1040 Description


The Anti-Lock Brake System (ABS) Module monitors the Rear Wheel Speed Sensor. Each time excessive wheel speed sensor acceleration or deceleration is detected, a fault counter increments. If the fault counter exceeds a specified value, the DTC will set.