OBD-II code · Powertrain (generic, extended)

P25F4 Turbocharger/Supercharger Boost Sensor C Circuit Low

The third boost pressure sensor signal is below the lower diagnostic threshold. Usually a shorted sensor element or a short to ground.

Is it safe to drive with P25F4?

Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.

Common causes

  • Most likelyInternal short in the sensor element
  • PossibleSignal wire shorted to ground
  • Less likelyConnector pins corroded - high contact resistance

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
Medium
DIY friendly
Often, with basic tools
Typical labour
0.5–2 h
Emissions test
Usually unaffected
Parts involved
Boost Pressure Sensor C, Wiring Harness

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