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.
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.
Common causes
- high
Open in sensor circuit
One of the most commonly reported causes for this code — check this first.
Typical part cost: $70-280
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
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Frequently asked questions
What does P04B8 mean?
P04B8 means "Fuel Fill Door Position Sensor Circuit". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P04B8?
open in sensor circuit — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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