C0045Brake Pressure Sensor B
- Generic OBD-II code · Chassis
- Can trigger limp mode
- How the car detects it
- C0045 covers brake pressure sensor B, the second pressure transducer in the ABS/ESC hydraulic unit next to sensor A (C0044). Two sensors let the module watch both brake circuits or check one reading against the other for stability control, brake assist and brake-by-wire functions. The code sets for a signal out of range, an open or short, or a value that disagrees with sensor A or the pedal demand. Where the sensor sits inside an integrated brake unit, repair usually means replacing the whole unit. NHTSA's EPS safety report lists C0045 with this J2012 meaning. Older GM vehicles use C0045 for the left rear wheel speed sensor circuit instead (GM PIE0456, 16-NA-248), so the make decides what a stored C0045 means.
- What you may notice
- ABS or brake warning lamp on
- Stability and assist functions disabled
- Changed brake assist behaviour
- Likely causes
- LikelyPressure sensor failed or out of range
- PossibleFault internal to the integrated brake unit
- RareSignal does not correlate with sensor A
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €400 – €2,200
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.