P04BCFuel Fill Door Lock Control Range/Performance
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- On plug-in hybrids with a sealed, pressurised tank, pressing the fuel button (open request) starts a refuelling mode: the module opens the tank valve, releases the pressure into the charcoal canister and only then unlocks the filler door via an electric actuator (Ford patent). P04BC concerns the lock circuit: the actuator is driven but the expected reaction is missing – the door or lock sensor reports no change within the time window. A separate lock output exists only on actuators that drive actively in both directions; spring-return actuators have only the unlock circuit. No manufacturer document available to us uses this code; the description follows CARB's rules for input and output components and patents on the door actuator.
- What you may notice
- Filler door does not open or lock as commanded
- Refuelling system message in the instrument cluster
- Possibly check engine light
- Likely causes
- LikelyActuator or door mechanically blocked (ice, dirt, bent door, cap tether)
- PossibleActuator worn or stiff
- PossibleLock or door sensor reporting wrongly
- PossibleDoor held or pressed by hand during actuation
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €0 – €250
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.