What it means
This code identifies a fault associated with brake pedal position sensor circuit B. The specific failure depends on the diagnostic subtype.
How it works
Brake pedal position sensor circuit B provides a separate pedal-position signal to the brake-control system. This code flags a subfault on circuit B specifically; it does not by itself say whether that signal is missing, intermittent, or outside its expected range.
Common causes
Most likely first.
- Faulty pedal position sensor
- Damaged wiring or connector
- Poor sensor power or ground
- Misadjusted sensor
- Brake control module fault
Symptoms
- ABS or brake warning light
- Stability control warning
- Cruise control may not work
- Unusual brake pedal response
How to diagnose it
- Read brake-control module codes and freeze-frame data, then watch live circuit B position data while moving the pedal through its travel.
- Inspect the circuit B connector and wiring at the pedal for corrosion, loose pins, chafing, or strain.
- Check sensor mounting and adjustment, and see whether circuit B changes smoothly and plausibly as the pedal is pressed and released.
- Test circuit B power, ground, and signal wiring using the vehicle diagram and manufacturer's procedure, including checks for intermittent opens or shorts.
- If circuit B wiring and adjustment pass, test the BPP sensor and brake-control module input for a circuit-specific failure.
Common fixes
- Reconnect or clean the circuit B connector.
- Repair a damaged circuit B wire or poor ground.
- Correct the BPP sensor mounting or adjustment.
- Replace the BPP sensor if its circuit B output fails testing.
- Repair the brake-control module only if its circuit B input is confirmed faulty.
Can I keep driving?
Stability control or cruise control may be unavailable, and brake-related control behavior may be abnormal. Drive only if the brakes feel normal and no brake warning requires stopping; get the circuit B fault checked promptly.
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.