C0040: Right front wheel speed sensor circuit
Drive carefully. Get it checked within a week or two.
Can I drive with C0040?
Yes, but drive carefully and get it checked soon. Right front speed sensor failure; ABS and traction control lights will illuminate.
What does C0040 mean?
C0040 stands for Right Front Wheel Speed Sensor Circuit Malfunction.
Symptoms you may notice
- ABS, Traction Control, and StabiliTrak warning lights illuminated
- Anti-lock pulse disabled during wet or panic stops (normal brakes work)
- Cruise control disabled by brake safety interlock
How much does it cost to fix?
Repair costs for code C0040 depend on the specific underlying root cause, ranging from simple DIY checks to component replacement. The table below lists the most common causes and rough price ranges in USD:
- Failing right front ABS wheel speed sensor
- Wiring harness snagged by road debris
- Corroded connector at wheel well liner
- Faulty wheel bearing assembly
What to do next
- Check the sensor harness clipped along the right front brake line.
- Clean metallic brake dust off the magnetic sensor tip.
- Replace the right front wheel speed sensor.
Last updated: October 2026
Related codes
General guidance only, not a professional diagnosis. If the check-engine light is flashing, or the car is running rough, overheating or losing power, stop driving and get help.
About this code
Code C0040 affects the right front wheel speed reading. The ABS and StabiliTrak/ESP warning lights will illuminate. You can drive safely on dry pavement, but allow extra stopping distance on slick surfaces.