What it means
Same as P04C3 with feedback in plausible range yet not matching the commanded lock state.
How it works
The lock-position sensor tells the module whether the fuel-fill door lock is engaged or released. P04C4 sets when the feedback is electrically plausible but does not match the commanded lock state, which can point to a misadjusted sensor or a latch that does not reach its expected position.
Common causes
Most likely first.
- Lock-position sensor misadjusted or drifting
- Loose or corroded sensor connection
- Binding lock mechanism preventing expected position
Symptoms
- Fuel-fill door lock status may be incorrect
- Door may not lock or unlock as expected
How to diagnose it
- Review freeze-frame data and compare scan-tool lock commands with position feedback to identify which commanded state fails to match.
- Inspect the fuel-fill door latch and linkage for binding, misalignment, or incomplete movement between locked and released positions.
- Check that the position sensor is secure and correctly aligned with the lock mechanism.
- Inspect the sensor connector and wiring for looseness or corrosion that could distort the feedback.
- Compare sensor response through lock and unlock commands with the manufacturer's specification.
Common fixes
- Correct a misaligned sensor or lock mechanism.
- Free or repair a binding latch or linkage.
- Clean and secure a loose or corroded sensor connection.
- Replace a sensor that drifts or fails to track the lock position.
Can I keep driving?
Driving is generally safe if the fuel-fill door is closed and secure, though its reported lock status may be wrong. Confirm the door latches properly and do not force it if the mechanism binds.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.