C0051 DTC: Right Rear Wheel Speed Sensor Performance
What Does C0051 Mean?
Diagnostic Trouble Code (DTC) C0051 indicates that the ABS control module has detected an abnormal performance condition with the right rear wheel speed sensor. Although the sensor circuit may be electrically functional, the signal is inaccurate, unstable, or inconsistent compared with the other wheel speed sensors, which can affect the operation of the ABS, Traction Control (TCS), and Electronic Stability Control (ESC).
Symptoms
- ABS warning light illuminated
- Traction Control (TCS) warning light ON
- Electronic Stability Control (ESC) warning
- Unexpected ABS activation during low-speed braking
- Traction Control disabled
- Cruise control may stop working on some vehicles
- Poor ABS performance during emergency braking
- Additional ABS-related DTCs stored
Common Causes
- Faulty right rear wheel speed sensor
- Damaged or cracked tone ring (reluctor ring)
- Incorrect sensor air gap
- Excessive wheel bearing play
- Metal debris attached to the magnetic sensor
- Damaged wiring harness or connector
- Loose electrical connections
- Faulty ABS control module (rare)
Typical Diagnostic Flow
How to Diagnose C0051
- Read ABS DTCs using a professional scan tool.
- Monitor live wheel speed data while driving.
- Compare the right rear wheel speed with the other three wheel speed sensors.
- Inspect the tone ring for cracks, rust, or missing teeth.
- Verify the sensor air gap meets manufacturer specifications.
- Inspect the wheel bearing for excessive movement.
- Check the sensor wiring and connector for corrosion or damage.
Typical Values
- All wheel speed sensors should report nearly identical speeds while driving in a straight line.
- Sudden signal dropouts or unstable readings indicate a sensor performance fault.
- Exact specifications vary by vehicle manufacturer.
Estimated Repair Cost
- Wheel speed sensor replacement: $70–250
- Wiring repair: $50–200
- Tone ring replacement: $80–300
- Wheel bearing replacement: $150–500
- ABS module replacement: $400–1,200
Related DTCs
- C0046
- C0047
- C0048
- C0049
- C0050
Frequently Asked Questions
Can I drive with C0051?
Yes. Normal braking remains available, but the ABS, Traction Control, and Stability Control systems may not function correctly until the fault is repaired.
What is the most common cause of C0051?
The most common causes are a faulty right rear wheel speed sensor, a damaged tone ring, excessive wheel bearing play, metal debris on the sensor, or damaged wiring and connectors.
Will clearing the DTC permanently fix C0051?
No. Clearing the code only removes it temporarily. If the underlying sensor performance problem remains, the ABS module will store the DTC again after the next drive cycle.