P04CD
Fuel Fill Door Open Request Sensor or Switch Stuck On
The open-request switch is stuck in the active state - the ECU continuously reads a request to open the fuel fill door. Either the switch is mechanically held closed or the line is shorted to its active level.
The open-request switch is stuck in the active state - the ECU continuously reads a request to open the fuel fill door. Either the switch is mechanically held closed or the line is shorted to its active level.
Common causes
- high
Switch contact mechanically stuck closed
One of the most commonly reported causes for this code — check this first.
Typical part cost: $70-240
- low
Carbon or debris buildup preventing free movement
Less common, but worth ruling out after the more likely causes.
Typical part cost: $70-240
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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
See related trouble codes
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Frequently asked questions
What does P04CD mean?
P04CD means "Fuel Fill Door Open Request Sensor or Switch Stuck On". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P04CD?
switch contact mechanically stuck closed; carbon or debris buildup preventing free movement; component wear with age - mechanical play — 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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