P25C5 code meaning
Brake Booster Temperature Sensor A Circuit Range/Performance
Powertrain system Generic code P25xx codes Check engine light
What P25C5 means
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.
P25C5 at a glance
- Check engine lightYes, usually on
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor1 to 4 hours
- Clears after repairAfter a drive cycle
Symptoms of P25C5
- Brake warning message, sometimes only after long braking
- Brake assistance reduced as a precaution
Common causes of P25C5
- Most likelySensor drifted out of its characteristic curve
- PossibleContact resistance at the booster connector skewing the signal
- Less likelyMeasurement error in the booster electronics
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Electric brake boosterTemperature sensor
What each part of P25C5 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 5 | Area: vehicle speed, idle control and auxiliary inputs. |
| C5 | The exact fault in that area. |
What to do next
- Note P25C5 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P25C5
What does P25C5 mean?
P25C5 means "Brake Booster Temperature Sensor A Circuit Range/Performance". 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. It is a generic code, so it means the same on every make.
Is it safe to drive with P25C5?
Drive gently and only to a workshop. With P25C5 the car can go into limp mode (reduced power) to protect itself.
Will P25C5 fail an emissions test?
P25C5 is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is P25C5 to fix?
Difficulty: workshop only. A typical repair takes 1 to 4 hours of work. This is a job for a workshop.
Will P25C5 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.