C003D code meaning
Rear Wheel Speed Sensor
What C003D means
Covers a single rear wheel speed sensor on vehicles that use one combined rear speed signal, for example a rear axle or differential-mounted sensor, instead of separate left and right rear sensors. It reports rear rotation to the ABS/ESC module for anti-lock, traction and stability control and electronic brake-force distribution. The module monitors the circuit for opens, shorts to power or ground, a signal outside the valid range and a missing signal while moving. A fault disables ABS, traction and stability control and lights the ABS warning lamp while base braking remains. No manufacturer documents this code publicly; NHTSA's EPS safety report carries C003D as the rear wheel speed sensor in its J2012 table.
C003D at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 2 hours
- Clears after repairWhen cleared with a scanner
Symptoms of C003D
- ABS warning lamp on
- ABS and stability control disabled
- Speedometer may read erratically
Common causes of C003D
- Most likelyRear wheel speed sensor failed
- PossibleOpen, shorted or chafed sensor wiring
- Less likelyCorroded sensor connector
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Rear wss
What each part of C003D means
| C | Chassis system: brakes, ABS, steering and suspension. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 3D | The exact fault in that area. |
What to do next
- Note C003D and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about C003D
What does C003D mean?
C003D means "Rear Wheel Speed Sensor". Covers a single rear wheel speed sensor on vehicles that use one combined rear speed signal, for example a rear axle or differential-mounted sensor, instead of separate left and right rear sensors. It is a generic code, so it means the same on every make.
Is it safe to drive with C003D?
Drive gently and only to a workshop. With C003D the car can go into limp mode (reduced power) to protect itself.
Will C003D fail an emissions test?
C003D is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is C003D to fix?
Difficulty: medium. A typical repair takes 0.5 to 2 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will C003D clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.