OBD-II code · Powertrain (generic, extended)

P25C5 Brake Booster Temperature Sensor A Circuit Range/Performance

The booster temperature sensor reading is implausible relative to commanded assist or coolant temperature. The signal moves too slowly, sticks, or never reaches expected values during operation.

Is it safe to drive with P25C5?

Usually safe for short trips, but don’t ignore it: the underlying fault can get more expensive over time.

Common causes

  • PossibleSensor drift or contamination on the temperature element
  • PossibleSensor not seated properly against the booster motor housing
  • Less likelySensor element aged beyond calibration window

Symptoms

  • Check engine light on
  • Significant power loss / limp mode
  • Possible blue or black smoke from exhaust
  • Whistling or hissing sound from intake

Repair at a glance

Difficulty
Hard
DIY friendly
Best left to a mechanic
Typical labour
1–3.5 h
Emissions test
Usually unaffected
Parts involved
Electric Brake Booster, Temperature Sensor

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.