P04C9: Fuel Fill Door Open Request Performance Stuck Off

What it means

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.

How it works

The fuel-fill door open-request switch should change state when pressed and return when released. P04C9 sets when the control module does not detect the active request, consistent with a switch contact that stays open or a broken input path.

Common causes

Most likely first.

1. Switch contact stuck open
2. Carbon or debris buildup preventing free movement
3. Component wear with age - mechanical play

Symptoms

• Fuel-fill door may not release when requested
• Open-request button may not respond

How to diagnose it

1. Check scan-tool live data for the open-request state while pressing and releasing the button to confirm it never registers.
2. Inspect the button for sticking, restricted movement, debris, or damage that could prevent the contact from closing.
3. Check the switch connector and nearby wiring for loose terminals, corrosion, or a break in the signal path.
4. Test switch continuity while operating the button and compare the result with the manufacturer's specification.
5. If the switch changes state correctly, trace the input wire to the control module and check continuity and terminal fit.

Common fixes

• Clear debris and free a button that is mechanically obstructed, if the switch is serviceable.
• Reconnect or repair loose or corroded switch terminals.
• Repair an open or damaged input wire.
• Replace the open-request switch if its contact fails to change state.

Can I keep driving?

You can usually drive if the fuel-fill door is secure, but confirm you can open it before you need fuel. The switch may continue to prevent door release.