Wheel Speed Sensor Fault (Rear Right)
The control module has detected a malfunction in the rear right wheel speed sensor.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The rear right wheel's sensor isn't sending the right signals about the wheel's speed, which can mess with your ABS and traction control systems.
What the computer is actually seeing
The ABS control module expects a voltage signal from the rear right wheel speed sensor typically between 0.5V to 2.5V when receiving normal readings. A signal dropout or unexpected voltage drop can occur due to bad wiring or a failed sensor.
What a healthy reading looks like
Voltage at the rear right wheel speed sensor should be between 0.5V - 2.5V while in motion; any reading below 0.5V indicates a fault.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Check the wiring harness for visible damage or corrosion. If damaged, repair or replace as necessary.
- 22. Inspect the connector at the sensor for corrosion or loose fit. Clean or reseat the connector if needed.
- 33. With the vehicle on the lift, measure the voltage at the rear right wheel speed sensor while spinning the wheel. Expected reading is 0.5V to 2.5V. If it's out of range, proceed to the next step.
- 44. If the sensor voltages are normal, check the ABS control module by retrieving any additional codes. If more codes are present related to ABS or stability control, further testing of the control module may be required.
- 55. If the wheel speed sensor has failed, replace the sensor and clear the codes.
Common causes
- Broken or corroded wiring
- Faulty wheel speed sensor
- Bad connector or loose connection at the sensor plug
- ABS control module failure
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's drivable but without ABS and traction control, you may experience decreased stability, especially in slippery conditions.
Will this code come back after clearing it?
Yes, if the root cause isn't fixed, the code will likely reappear.
Why does this code pair with other C123X codes?
They often indicate issues with other wheel speed sensors or related wiring, affecting overall ABS function.
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