What it means
Right Front Wheel Speed Sensor B Intermittent/Erratic: the signal is intermittent or erratic. 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
Right front wheel speed sensor B reports wheel rotation to the ABS module, which uses the signal for braking and stability functions. This code sets when the B signal becomes intermittent or erratic, often as a loose or oxidized connector or a vibrating harness interrupts contact.
Common causes
Most likely first.
- Connector loose or oxidized
- Connector with intermittent contact under vibration
- Harness routed against vibrating component
Symptoms
- ABS warning light on
- ESC/stability control deactivated
- Possible reduced brake assist
- Speedometer may behave erratically
How to diagnose it
- Save the ABS freeze-frame data and compare live right front sensor B speed with the other wheels during slow movement.
- Inspect the right front B connector for looseness, oxidation, or terminals that may lose contact when vibrated.
- Trace the sensor B harness and check whether it touches a vibrating component, rubs, or is inadequately secured.
- With live data displayed, gently move the B connector and harness to see whether the reading drops out.
- If the interruption persists, test the sensor B circuit and sensor output under the manufacturer's procedure, then check the ABS module connection if the harness passes.
Common fixes
- Secure the right front sensor B connector and restore terminal tension where needed.
- Clean corrosion or replace damaged terminals and connector seals.
- Reroute and secure the harness away from vibrating or rubbing parts; repair damaged insulation.
- Replace sensor B if it continues to produce an erratic signal after circuit checks.
Can I keep driving?
Drive gently because ABS and stability or traction control may cut out unexpectedly, and braking assistance may be reduced. Avoid slippery roads and hard braking until the intermittent signal is fixed.
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.