P04B5
Fuel Fill Door Stuck Open
On vehicles with a motorised fuel fill door (no manual lever) the actuator and position switch report that the door is mechanically stuck open. The motor cannot retract it, typically due to a frozen or dirty hinge, broken cable, or jammed actuator.
- Check engine light: Not always
- Emissions related: No
- Repair difficulty: easy
Common causes
Ordered by how often each turns out to be the cause.
- Hinge jammed by ice, dirt or debrisCommon
- Actuator linkage or motor brokenPossible
- Carbon or debris buildup preventing free movementLess likely
Parts involved
- Fuel Fill Door
- Fuel Fill Door Actuator
P04B5 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.