P25FDTurbocharger/Supercharger Bypass Valve C Temperature Too High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- This code says bypass valve C has become too hot. Recirculation valves are placed in the charge air path close to the compressor and thus near the hot turbine side, and an electric valve's coil adds its own heat when energised for long periods. How the engine module learns the temperature – a sensor in the valve or an estimate from current and duty cycle – is not stated in any public manufacturer document, and none documents P25FD itself. To protect the coil the module will usually limit or stop driving the valve, which can then lead to surging on lift-off or reduced boost. Separate codes cover the same overheating for valves A and B (P00D7, P00D8); a valve that is jammed rather than overheated is P25FC.
- What you may notice
- Check engine lamp on
- Fluttering on lift-off or reduced boost after hard driving
- Likely causes
- LikelyHeat soak from the turbocharger, e.g. after hard driving or with missing heat shields
- PossibleValve coil drawing too much current due to an internal fault
- RareSluggish valve held energised longer than intended
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €800
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.