What does it mean?
This code is stored when the module sees the fuel filler door lock control circuit at a higher voltage than expected while it is driving the output, or finds voltage present when the output should be off. From the module's perspective the current it commanded never flowed, which happens with an open circuit, and it also happens when an outside supply holds the line high. The distinction matters because the repairs are completely different, and only measurement at the connector will separate them. With the output disabled the door lock function is lost, and vehicles that require a confirmed locked filler door for their evaporative strategy will hold those tests as well. Connector corrosion in this exposed location is a frequent starting point for the fault.
Symptoms
- Fuel filler door does not lock and does not respond to a lock command
- MIL (check engine lamp) on with fuel filler door lock circuit codes
- No sound from the actuator during a scan tool output test
- Live data shows the lock as unlocked regardless of the command
- Evaporative monitors not completing on vehicles that require a locked door
- Fault frequently appears after work in the rear of the vehicle
Likely causes
- Open control or supply wire between the module and the lock actuator
- Open winding inside the lock actuator after water intrusion or age
- Terminal backed out of the connector, or a connector never fully latched after service
- High resistance from heavy corrosion, read by the module as an open circuit
- Control wire shorted to a battery voltage feed running in the same loom
- Blown fuse or an open relay contact on the actuator supply
- Module driver stage failed open, only after external circuit checks pass
How to fix it
- Verify the fault is present, then perform an output test and listen at the actuator
- Unplug the actuator and measure winding resistance; an infinite value identifies an internally open actuator
- With the ignition on and the actuator unplugged, check for unexpected battery voltage on the control wire
- Test continuity of the control wire from the module connector to the actuator connector
- Check the supply fuse and any relay feeding the circuit, because a missing feed reads the same way
- Inspect both connectors for corrosion, water damage, melted plastic and terminals out of their locks
- Repair the wiring or replace the actuator as indicated, then clear the code and confirm the lock operates on every cycle