What it means
Same as P04BB with the control line shorted to supply. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
How it works
The fuel-fill door lock is operated by an actuator, and its control module switches the actuator's control line to command locking. P04BE sets when the module detects that lock-control line at a higher electrical level than expected, such as when it is shorted to a supply source.
Common causes
Most likely first.
- Control line shorted to supply
- Connector pins corroded - high contact resistance
- Supply wire pinched against B+ source
Symptoms
- Fuel-fill door may not lock
- Fuel-fill door warning or status may be incorrect
How to diagnose it
- Check scan-tool freeze-frame data and fuel-door lock command or status to confirm the fault occurred during a lock request.
- Inspect the lock actuator connector and nearby harness for water, corrosion, pushed-back pins, chafing, or a wire pinched against a power source.
- With the circuit active, gently move the harness while watching the scan-tool status to see whether the fault changes.
- Use the vehicle wiring diagram to test the lock-control line for an unintended connection to supply, following the manufacturer's procedure.
- If the wiring and connector pass inspection, test the actuator and module output against the manufacturer's specification.
Common fixes
- Clean and secure a loose or corroded actuator connector.
- Repair chafed or pinched wiring that is contacting a supply circuit.
- Replace a damaged connector terminal or seal that is allowing water in.
- Replace the lock actuator or repair the module only if testing confirms it is faulty.
Can I keep driving?
The vehicle may remain drivable, but the fuel-fill door may not lock and its status warning may be unreliable. Avoid leaving the vehicle unattended if the door will not secure, and arrange repair before relying on the lock.
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.