Worn or misadjusted fuel fill door open request switch; Damaged or chafed wiring harness at the fuel door hinge area; Corroded or loose electrical connector at the switch or body control module; Water intrusion into the switch or connector causing erratic resistance; Failed body control module (BCM) or PCM input circuit; Aftermarket alarm or remote start installation tapping into the circuit

DTC codes / P04xx · Auxiliary emission controls / P04CC

P04CCFuel Fill Door Open Request Sensor/Switch Circuit Intermittent/Erratic

P04CC indicates that the powertrain control module (PCM) has detected an intermittent or erratic signal from the fuel fill door open request sensor or switch circuit. The PCM expects a stable voltage or resistance from this circuit when the fuel door is opened or closed, and it flags the code when the signal jumps, drops out, or behaves unpredictably over a short period.

SystemPowertrain

Code typeGeneric (all makes)

SeverityLow

Fix difficultyIntermediate

AreaAuxiliary emission controls

Symptoms you may notice

Illumination of the check engine light or service vehicle soon message
Fuel door open warning displayed when the door is actually closed
Fuel door open warning fails to appear when the door is opened
Remote or central locking may not recognize the fuel door state
Often no symptoms besides the warning light
Intermittent operation of fuel door-related convenience features

Common causes, most likely first

Worn or misadjusted fuel fill door open request switch
Damaged or chafed wiring harness at the fuel door hinge area
Corroded or loose electrical connector at the switch or body control module
Water intrusion into the switch or connector causing erratic resistance
Failed body control module (BCM) or PCM input circuit
Aftermarket alarm or remote start installation tapping into the circuit

How to diagnose and fix it

Inspect the fuel fill door switch for physical damage, contamination, or sticking
Check the wiring harness and connector at the fuel door for chafing, corrosion, or loose pins
Measure the switch resistance or voltage in both open and closed positions and compare to specification
Wiggle-test the harness while monitoring the switch signal on a scan tool to detect intermittent faults
Verify the ground and power supply to the switch circuit
If the switch and wiring are good, test the BCM or PCM input circuit and reprogram or replace as needed
Clear the code and perform a road test to confirm the repair

Intermittent fuel door switch faults

A fuel fill door switch that tests fine when stationary can still set P04CC due to vibration or temperature changes affecting internal contacts.
Water and road salt often accumulate at the fuel door hinge, causing corrosion that creates erratic signals without a complete failure.
The code can be set by a loose fuel cap or aftermarket fuel door accessory that interferes with the switch mechanism.
Technicians sometimes replace the switch only to find the connector pins are spread or the wire is broken inside the insulation near the hinge.
P04CC is often stored alongside other body or communication codes if the BCM is involved, so a full system scan is essential.

Can I keep driving with P04CC?

The vehicle remains safe to drive because this circuit affects only the fuel door status indication and related convenience features. Avoid pressing or forcing the fuel door and schedule a diagnostic inspection at your earliest convenience to prevent misdiagnosis of related systems.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.