What it means
Right Rear Wheel Speed Sensor B Range/Performance: the signal is implausible or outside the valid range. Wheel-speed signals feed ABS, ESC, traction control and the speedometer.
At a glance
- Usually lights the ABS or stability-control warning light
- The engine or gearbox may go into limp mode
How it works
The right rear wheel speed sensor B provides a signal that the ABS control module checks for plausible speed and signal quality. This code sets when the right rear reading falls outside the valid range or behaves implausibly, which can happen if the tone ring is damaged, the sensor is worn, or its mounting weakens the signal.
Common causes
Most likely first.
- Tone ring damaged or contaminated
- Sensor element aged beyond calibration window
- Sensor mounting loose - signal damping
Symptoms
- ABS warning light on
- ESC/stability control deactivated
- Possible reduced brake assist
- Speedometer may behave erratically
How to diagnose it
- Capture freeze-frame data and compare live right rear sensor B speed with the other wheels, looking for a reading that is consistently implausible or changes with speed.
- Inspect the right rear sensor B wiring and connector for looseness, damage, or contamination.
- Examine the right rear tone ring or encoder for dirt, cracking, missing features, or other damage.
- Check that sensor B is firmly mounted and positioned to meet the manufacturer's specified gap.
- If the mechanical condition and mounting are sound, test sensor B output and its wiring using the manufacturer's procedure.
Common fixes
- Clean contamination from the right rear tone ring or encoder if appropriate.
- Secure and correctly position the right rear sensor B mounting.
- Repair loose or damaged sensor B wiring and connector terminals.
- Replace the damaged encoder or sensor if inspection and testing identify it as the source.
Can I keep driving?
ABS and stability or traction control may be disabled, and the speedometer may be unreliable. Drive gently with extra stopping distance and avoid slippery roads until the right rear signal is within the expected range.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.