GM Service Manual Online
For 1990-2009 cars only

Fuel Fill Door Description and Operation with Theft Deterrent System

Fuel Door Release System Components

    • Body control module (BCM)
    • Fuel door release actuator
    • Fuel door relay

The locking and unlocking of the fuel door is a function of the power door lock system. The fuel door release actuator is supplied by the door lock signal circuit and the driver door unlock signal circuit which is switched through the fuel door relay. The fuel door relay coil is controlled by the body control module (BCM). When the vehicles doors are unlocked, the body control module (BCM) will respond by applying voltage to the fuel door relay coil control circuit. This energizes the coil causing the switch contacts to close. With the switch contacts closed, the driver door unlock circuit supplies B+ or ground to the fuel door release actuator , unlocking the fuel door.

Fuel Fill Door Description and Operation without Theft Deterrent System

Fuel Door Release System Components

    • Body control module (BCM)
    • Fuel door relay

The locking and unlocking of the fuel door is a function of the power door lock system. The fuel door release actuator shares the circuit with the driver door latch. The body control module (BCM), upon receipt of a lock switch lock or unlock signal, will switch the appropriate door latch, as well as a fuel filler door release actuator control circuits to B+ voltage. The opposing side of the door latch and fuel filler door release actuator is connected to ground provided by the BCM through the other the door latch control circuits, along with the fuel filler door release actuator, will lock or unlock as commanded.