OBD-II code · Powertrain (generic, extended)
P25F9 Turbocharger/Supercharger Bypass Valve C Control Circuit Low
Voltage on the third bypass valve control line is below the expected window. Usually a short to ground or a shorted solenoid coil.
Is it safe to drive with P25F9?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyControl wire shorted to ground
- PossibleInternal short in the solenoid coil
- Less likelyConnector pins corroded - high contact resistance
Symptoms
- Charge status indicator shows fault
- Charging may not start or interrupts
- Slower-than-expected charge rate
Repair at a glance
- Difficulty
- Medium
- DIY friendly
- Best left to a mechanic
- Typical labour
- 0.8–3 h
- Emissions test
- Usually unaffected
- Parts involved
- Bypass Valve C, Bypass Solenoid, Wiring Harness
Related codes
- P00C1Turbocharger/Supercharger Bypass Valve B Control Circuit Low
- P25F6AIR System B
- P25F7AIR System B Incorrect Flow Detected
- P25F8Turbocharger/Supercharger Bypass Valve C Control Circuit
- P25FATurbocharger/Supercharger Bypass Valve C Control Circuit High
- P25FBTurbocharger/Supercharger Bypass Valve C Control Circuit Range/Performance
- P25FCTurbocharger/Supercharger Bypass Valve C - Mechanical
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.