What it means
Right Front Wheel Speed Sensor B Circuit Low: the signal voltage is below the expected 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
Right front wheel speed sensor B sends a signal to the ABS module, which monitors the circuit level as well as wheel rotation. This code sets when the B circuit voltage is below the expected range, commonly from a short to ground, corroded contact, or chafed wire.
Common causes
Most likely first.
- Signal wire shorted to ground
- Connector pins corroded - high contact resistance
- Harness chafing through insulation
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 inspect live right front sensor B data for a missing or implausible reading.
- Inspect the right front B harness for chafing through its insulation, especially where it passes near the wheel or body.
- Check the sensor B connector pins for corrosion, poor contact, or moisture that could increase resistance.
- Test the B signal wire for a short to ground and check connector and sensor circuit continuity using the manufacturer's procedure.
- If wiring and terminals pass, test the sensor B output and ABS module input against the manufacturer's specification.
Common fixes
- Repair chafed insulation on the right front sensor B harness and secure it away from contact points.
- Clean corrosion and restore sound terminal contact at the sensor B connector.
- Replace damaged connector terminals or wiring that tests shorted to ground.
- Replace sensor B only if its circuit output remains below specification with wiring verified.
Can I keep driving?
Drive cautiously because ABS and stability or traction control may be unavailable, and braking assistance may be reduced. Avoid slippery roads and hard braking until the low circuit reading is repaired.
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.