C05C4Brake Pressure Sensor F Missing Calibration
- Generic OBD-II code · Chassis
- Can trigger limp mode
- How the car detects it
- The brake controller finds no stored calibration (offset or zero point) for pressure sensor F, the sixth hydraulic pressure sensor in its numbering. Which physical sensor carries the letter F is up to the maker, and none publishes C05C4. Comparable codes exist for sensors A and B: GM checks sensor B in its hybrid brake controller via test pulses after offset compensation, and Saab/GM calls for a scan-tool pressure sensor calibration after replacing the EBCM or the modulator. Hitachi learns pressure sensor zeros only while the master cylinder is pressureless and the pedal is released. A new module or hydraulic unit without the follow-up calibration is the usual cause. C05C5 to C05C8 cover the sensor's signal faults.
- What you may notice
- ABS, ESC or brake warning lamp on
- Stability control or brake assist functions disabled
- Likely causes
- LikelyCalibration skipped after module or hydraulic unit replacement
- PossibleCalibration interrupted by brake application or low voltage
- RareCalibration data lost in the module memory
- Repair
- Medium · Usually a job for a workshop.Typical cost: €50 – €300
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.