What does code P04FC mean?

Q: What does code P04FC mean?

Crankcase Ventilation System Performance. P04FC indicates that the powertrain control module has detected a performance fault in the crankcase ventilation system, which is responsible for routing blow-by gases from the crankcase back into the intake for combustion. The computer monitors this system through pressure sensors, flow models, or a dedicated sensor and sets the code when the measured or inferred crankcase pressure or flow falls outside the expected range for the current engine operating conditions.

DTC codes / P04xx · Auxiliary emission controls / P04FC

P04FCCrankcase Ventilation System Performance

P04FC indicates that the powertrain control module has detected a performance fault in the crankcase ventilation system, which is responsible for routing blow-by gases from the crankcase back into the intake for combustion. The computer monitors this system through pressure sensors, flow models, or a dedicated sensor and sets the code when the measured or inferred crankcase pressure or flow falls outside the expected range for the current engine operating conditions.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaAuxiliary emission controls

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