What it means
This code identifies a fault associated with brake pressure sensor B. The specific failure depends on the diagnostic subtype.
How it works
Brake pressure sensor B supplies a pressure reading to the brake-control system for functions such as anti-lock braking and stability control. This code identifies a subfault associated with sensor B specifically, but the base code does not state the subtype or exact failure mode.
Common causes
Most likely first.
- Faulty brake pressure sensor
- Damaged wiring or connector
- Corrosion at connector
- Poor sensor power or ground
- Brake control module fault
Symptoms
- ABS or brake warning light
- Stability control warning
- Reduced stability control
- Unusual braking feel
How to diagnose it
- Read brake-control module codes and freeze-frame data, then observe live sensor B pressure data as the brake pedal is applied and released.
- Inspect sensor B's connector and harness for corrosion, loose terminals, fluid contamination, or damage.
- Check the sensor's mounting and the surrounding brake hydraulics for visible leakage or impact damage without opening the hydraulic circuit.
- Test sensor B's power, ground, and signal wiring using the vehicle diagram and manufacturer's procedure.
- If the wiring passes, test sensor B's pressure reading against the manufacturer's diagnostic method and verify the module input.
Common fixes
- Reconnect or clean sensor B's connector.
- Repair damaged sensor B wiring or a poor power or ground connection.
- Replace brake pressure sensor B if its signal fails testing.
- Repair the brake-control module only if the sensor B input is confirmed faulty.
Can I keep driving?
ABS or stability control may not work as intended, and unusual braking feel needs prompt attention. Stop safely if the pedal feels abnormal or braking performance changes, and have the pressure-sensing fault diagnosed before continuing.
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.