C050B code meaning
Right Front Wheel Speed Sensor A Correlation
Chassis system Generic code C05xx codes Check engine light
What C050B means
C050B is the correlation code for the right front wheel. GM's 2025 tables (25OBDG04A) rate it Type B, so the MIL waits for a second trip, and add a check not found under C0505 in the 2019 tables: the brake module compares the switching state it requests from the sensor supply driver with the state reported back, an internal module fault rather than a sensor problem. The plausibility checks stay: from start-up to 15 km/h a wheel below 1.2 km/h counts as missing, and if only this wheel exceeds 6 km/h while another stays under 1.5 km/h, a 40 s wait precedes storing the fault. Mitsubishi lists C1063-64 as C050B, naming tire size and sensor rotor. Bosch's active sensors resolve speed down to about 0.1 km/h, so a dead channel shows up early.
C050B at a glance
- Check engine lightYes, usually on
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyEasy, DIY possible
- Typical labor0.3 to 2 hours
- Clears after repairAfter a drive cycle
Symptoms of C050B
- ABS/ESC lamps after the second drive with the fault
- Stability and traction control unavailable, normal braking retained
Common causes of C050B
- Most likelyRight front tire of a different size or circumference
- PossibleSensor-to-ring gap out of tolerance or demagnetized encoder
- Less likelyInternal fault in the ABS module's sensor supply switch (GM)
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Wss rfTone ring rfTiresABS control module
What each part of C050B means
| C | Chassis system: brakes, ABS, steering and suspension. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 0B | The exact fault in that area. |
What to do next
- Note C050B 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 C050B
What does C050B mean?
C050B means "Right Front Wheel Speed Sensor A Correlation". C050B is the correlation code for the right front wheel. It is a generic code, so it means the same on every make.
Is it safe to drive with C050B?
Drive gently and only to a workshop. With C050B the car can go into limp mode (reduced power) to protect itself.
Will C050B fail an emissions test?
C050B 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 C050B to fix?
Difficulty: easy. A typical repair takes 0.3 to 2 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will C050B clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.