Faulty fuel fill door lock actuator (internal short or fault); Control circuit shorted to voltage, or damaged wiring near the filler flap or boot hinge area; Corroded, wet or loose connector at the actuator or control module; Mechanical binding or a frozen or damaged flap mechanism affecting the actuator; Faulty control module driver circuit; Outdated or faulty module software, where the manufacturer lists it as a known cause for the model.

P04BE

Fuel Fill Door Lock Control Circuit High.

Generic
Powertrain
Generic code
Low severity

How this code is built

P: SystemPowertrain
0: Defined bySAE, the same on every car
4: AreaAuxiliary emission controls
BE: FaultThe specific fault in that area

What it means

P04BE is the generic code for a high condition in the fuel fill door lock control circuit. The control unit drives the lock actuator that secures the fuel filler flap on vehicles with an electronically controlled door, and it saw a voltage higher than expected on that control circuit. The exact circuit design and which module sets the code depend on the model.

Symptoms

Malfunction indicator lamp on, or a fuel system warning shown on the dash
Fuel filler flap will not open, or will not lock
Fuel filler flap stays unlocked after the car is locked
Flap release button or central locking operation seems inconsistent
Possible difficulty refuelling

Possible causes

Faulty fuel fill door lock actuator (internal short or fault)likely
Control circuit shorted to voltage, or damaged wiring near the filler flap or boot hinge arealikely
Corroded, wet or loose connector at the actuator or control modulepossible
Mechanical binding or a frozen or damaged flap mechanism affecting the actuatorpossible
Faulty control module driver circuitrare
Outdated or faulty module software, where the manufacturer lists it as a known cause for the modelrare

How to diagnose

Read all stored and pending codes and note the freeze frame data, then check for other body or central locking codes
Operate the flap by hand and with the release control, listening for the actuator and checking for physical binding, dirt or ice
Inspect the actuator, its connector and the wiring through the flap and boot hinge area for chafing, corrosion and water ingress
Check the actuator connector pins for tension, green corrosion and bent terminals
Using the wiring diagram for the vehicle, measure supply, ground and control circuit voltage at the actuator connector with the system commanded on and off
Check the control circuit for a short to voltage and for continuity back to the module
Test the actuator resistance against the manufacturer specification, or test it with a fused external supply if the procedure allows
Check for a software update or technical bulletin for the model if wiring and actuator test fine

How to fix

Replace the fuel fill door lock actuator if it has failed internally
Repair or replace damaged wiring and renew the affected section of loom
Clean, dry and repair or replace corroded or damaged connectors and terminals
Free, lubricate or replace a stuck or damaged flap mechanism
Replace or repair the control module only after the wiring and actuator are proven good
Update the module software if a known fault is documented for the vehicle

Can I keep driving?

Low severity

The car can normally be driven as the fault does not affect engine running, but book it in soon. If the flap will not open you may struggle to refuel, so check the manual for the manual release before the tank gets low.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.