OBD-II code · Powertrain (generic)
P04B8 Fuel Fill Door Position Sensor Circuit
A general circuit fault is detected on the fuel fill door position sensor or switch - the ECU cannot determine whether the door is open or closed. Usually an open in supply, signal or ground.
Is it safe to drive with P04B8?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyOpen in sensor circuit
Repair at a glance
- Difficulty
- Easy
- DIY friendly
- Often, with basic tools
- Typical labour
- 0.4–1.2 h
- Emissions test
- Usually unaffected
- Parts involved
- Fuel Fill Door Position Sensor
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.