C0025 Brake Pedal Feedback Pressure Sensor Circuit

C0025 covers the pressure sensor on the pedal feedback side of a decoupled or brake-by-wire system, the measuring partner of the feedback valve C0024. In such systems the pedal pushes fluid into a pedal feel simulator via a simulator valve the module can open or close, while separate sensors read pressure in the simulator circuit and in the wheel circuit. A patent for this layout reads the driver's request from a pressure sensor on the master cylinder side and describes a standstill self-test that opens the simulator valve and watches the pressure rise. The module sets C0025 for a signal out of range, an open or short, or a value that does not fit pedal travel. Pedal feel changes, assist may drop to a mechanical fallback, and the brake or ABS lamp lights. No manufacturer documents this code publicly.

Likely causes

Symptoms

• Changed or abnormal pedal feel
• Loss of brake assist, driver messages
• ABS or brake warning lamp on

Repair estimate

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

Related codes

References: patents.google.com, en.wikipedia.org.