P25C5Brake Booster Temperature Sensor A Circuit Range/Performance
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- P25C5 is the plausibility fault for brake booster temperature sensor A: the circuit is electrically intact, but the reported temperature does not fit, for example a value that jumps implausibly, stays frozen while the motor works hard, or disagrees with the second sensor. No manufacturer documents P25C5 publicly. GM takes a different route on the 2023 Corvette Z06: rather than a separate rationality code, table 23OBDG07 adds up the signal voltages of temperature sensors 1 and 2 and logs the motor code C0582 as Type A once the sum exceeds 3.4 V for 0.6 s. That shows how two sensors can be checked against each other. A drifting sensor is the real hazard here, because the over-temperature protection of the electric motor relies on it.
- What you may notice
- Brake warning message, sometimes only after long braking
- Brake assistance reduced as a precaution
- Likely causes
- LikelySensor drifted out of its characteristic curve
- PossibleContact resistance at the booster connector skewing the signal
- RareMeasurement error in the booster electronics
- Repair
- Workshop only · Usually a job for a workshop.Typical cost: €150 – €2,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.