All codes/P04C9

P04C9

Fuel Fill Door Open Request Performance Stuck Off

Moderate severity

The open-request switch never registers an active state - either the contact stays open mechanically or the wiring is permanently broken. The driver cannot trigger door release.

The open-request switch never registers an active state - either the contact stays open mechanically or the wiring is permanently broken. The driver cannot trigger door release.

Common causes

  • Switch contact stuck open

    One of the most commonly reported causes for this code — check this first.

    high

    Typical part cost: $70-240

  • Carbon or debris buildup preventing free movement

    Less common, but worth ruling out after the more likely causes.

    low

    Typical part cost: $70-240

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First things to check

  1. 1Confirm the code with a scan tool and check for additional related codes.
  2. 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 P04C9 mean?

P04C9 means "Fuel Fill Door Open Request Performance Stuck Off". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.

What are the most common causes of P04C9?

switch contact stuck open; 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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