Principles of Operation (How Does it Work?)

The Generic Electronic Module (GEM) receives inputs and delivers outputs to many of the electronically controlled features of the vehicle. The GEM constantly monitors the system under its control and reports a concern in the form of a Diagnostic Trouble Code (DTC).

Power Door Locks
Regardless of the ignition switch position, the GEM is hot at all times. When the GEM receives a signal from the keyless entry remote transmitter or door lock control switch, the GEM supplies a ground signal to the appropriate lock or unlock relay. The ground signal closes the relay which supplies power to the door lock actuators. The door lock actuators will then actuate to a lock or unlock position determined by the relay power supplied on the lock or unlock circuit. The liftgate is also controlled by the GEM by sending a ground signal to the liftgate unlock relay. The liftgate unlock actuator is also hardwired to the liftgate relay. When the relay receives the ground signal from the GEM, it actuates the liftgate unlock actuator to the unlock position.

Smart Locks
The smart lock feature prevents the doors from locking with the key in the ignition. When the GEM receives a lock command from a door lock control switch, and the key is in the ignition switch with the driver door open, the GEM will command the all doors unlock relay on by grounding the relay after the lock has occurred.

Autolocking
The autolocking feature locks all doors when all doors (including liftgate) are closed, the ignition is in run, the transmission is in either a forward or reverse gear and vehicle speed is 5 kph (3 mph) or higher. If any door becomes ajar, this feature will relock all doors when the ajar door is returned to a closed position and all previous conditions are met.

Luggage Compartment Release
The luggage compartment release unlatches the luggage compartment lid when the customer requests it to be opened using the keyless entry remote transmitter or the interior luggage compartment release button which is hardwired to the GEM. When the GEM receives a ground signal to open the luggage compartment, it will in turn output a ground signal to the luggage compartment release relay. The ground signal closes the relay which supplies power to the luggage compartment release solenoid. The solenoid then actuates to release the lid.

Keyless Entry
The keyless entry keypad is hardwired to the GEM. The GEM interprets the inputs from the key less entry keypad and then controls the associated operation. The keyless entry keypad will be illuminated for five seconds when any button is pressed. Additionally, it will request the illuminated entry feature to turn the courtesy lamps on. If a lock all doors code is entered, the illumination will turn off, as well as request the illuminated entry feature to turn off the courtesy lamps. When pressed, the keyless entry keypad supplies the ground signal to the GEM or the GEM receives a signal from the key less entry remote transmitter. Then the GEM outputs a ground signal to the appropriate lock or unlock relay which supplies the power to the actuator to lock or unlocks all doors, including the luggage compartment. The keyless entry remote transmitter also unlocks the liftgate or activates the panic alarm by sending a signal to the GEM.