C003B code meaning
Right Rear Wheel Speed Sensor Supply
What C003B means
Covers the supply circuit that powers the right rear active wheel speed sensor, completing the supply set with C0032 and C0038. Active sensors need a regulated voltage from the ABS/ESC module; this code is set when that supply is open, shorted to ground or to another voltage, or outside the regulated range so the sensor cannot produce a valid signal. It is distinct from the sensor-signal code C003A in that the fault is on the feed rather than in the sensor element. A fault disables ABS, traction and stability control for that corner and lights the ABS warning lamp while base braking remains. No manufacturer documents this code publicly; NHTSA lists C003B as right rear supply in the J2012 table of its EPS safety report.
C003B 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 C003B
- ABS warning lamp on
- ABS and stability control disabled
- No wheel speed signal from this corner
Common causes of C003B
- Most likelyOpen or shorted sensor supply wire
- PossibleCorroded connector on the supply side
- Less likelyModule sensor supply output fault
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Rr wssSensor supply
What each part of C003B means
| C | Chassis system: brakes, ABS, steering and suspension. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 3B | The exact fault in that area. |
What to do next
- Note C003B 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 C003B
What does C003B mean?
C003B means "Right Rear Wheel Speed Sensor Supply". Covers the supply circuit that powers the right rear active wheel speed sensor, completing the supply set with C0032 and C0038. It is a generic code, so it means the same on every make.
Is it safe to drive with C003B?
Drive gently and only to a workshop. With C003B the car can go into limp mode (reduced power) to protect itself.
Will C003B fail an emissions test?
C003B 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 C003B 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 C003B clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.