Power Door Locks

WARNING: This page is about a different car, the 2003 Mazda Tribute. However, it is still accessible from the selected car via links, so may be relevant.

The generic electronic module (GEM) controls the power door lock and keyless entry system. Lock and unlock operation is achieved through the use of internal relays in the GEM. The relays are all door lock, all door unlock and driver door unlock. The normal path of the relays is to ground.

Pressing the door lock control switch to lock or unlock sends a ground signal to the GEM. The same GEM pin is used for unlock and lock input. The unlock signal is a direct connection to ground. The lock signal is altered by an internal resistor in the door lock control switch. This varied resistance identifies lock or unlock command to the GEM.

The door locks can also be controlled by the door key cylinder switches. For the liftgate door lock switch, turning the key to lock or unlock sends a ground signal to the GEM. The GEM will then ground the all door lock or all door unlock relay supplying voltage to the actuators. Turning the driver door key cylinder to the lock position sends a ground signal to the GEM. The GEM will then ground the all door lock relay supplying voltage to the actuators. Turning the driver door key cylinder to unlock sends a ground signal to GEM. The GEM will ground the driver door unlock relay and supply voltage to only the driver door actuator. If a second unlock ground is received within three seconds of the first, the GEM will ground the all door unlock relay supplying voltage to the passenger door actuators (if equipped with two stage unlock).