What does code P25F9 mean?

DTC codes / P25xx · Vehicle speed, idle control and auxiliary inputs / P25F9

P25F9Turbocharger/Supercharger Bypass Valve C Control Circuit Low

P25F9 indicates that the powertrain control module (PCM) has detected a low-voltage condition on the control circuit for the bypass valve of turbocharger or supercharger 'C'. The PCM commands the valve to open or close, but the circuit voltage is below the expected threshold, indicating a short to ground, an open circuit, or a faulty valve actuator.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaVehicle speed, idle control and auxiliary inputs

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.