P04CD
- Powertrain
- Generic (SAE)
Not urgent
Unlikely to affect driveability. Worth resolving so the light does not mask a future fault.
Fuel Fill Door Open Request Sensor or Switch Stuck On
This code is in our catalogue but has not yet been through editorial review, so the guidance below is limited to what our structured data supports. We publish deeper diagnostic content only after a code has been reviewed — here is why.
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.
A trouble code records what a control module measured. It does not identify which part failed. Test before replacing anything.
- Safe to drive
- Unlikely to affect driveability. Worth resolving so the light does not mask a future fault.
- Urgency
- Not urgent
- Will it pass emissions
- Not affected
- Check engine light
- Varies
| # | Cause | How often | Component |
|---|---|---|---|
| 1 | Switch contact mechanically stuck closed | Very common | — |
| 2 | Carbon or debris buildup preventing free movement | Occasional | — |
| 3 | Component wear with age - mechanical play | Occasional | — |
Ordering reflects how often each cause is responsible in general, not a probability for your vehicle. Confirm by testing.
- Fuel Fill Door Request Switch
- Definition
- Generic code set (SAE J2012 / ISO 15031-6) via the OBDexopen database, dedicated to the public domain under CC0-1.0.
- Diagnostic guidance
- Written and reviewed in-house. See our editorial policy.
- Review status
- Awaiting review
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