GM Service Manual Online
For 1990-2009 cars only

Keyless entry allows you to operate the following components:

    • The door locks.
    • The trunk lid release
    • The illuminated entry lamps
    • The panic alarm (instant alarm)
    • The radio personalization features

The keyless entry system has the following main components:

    • The transmitters
    • The body control module (BCM)

When you press a button on a transmitter, the transmitter sends a signal to the BCM. The BCM interprets the signal and activates the requested function. When the unlock button is pressed, the BCM sends a class 2 serial data message to the radio identifying that transmitter. The class 2 message will identify transmitter 1 and transmitter 2 separately, and the radio will activate the personalization settings accordingly. The class 2 message will also identify transmitter 3 and transmitter 4 separately, but the radio will use the same personalization settings for both identifications.

Unlock Driver's Door Only

When the unlock button of the transmitter is pressed momentarily, the BCM receives a signal and supplies battery voltage to the left front door lock motor. At the same time, the BCM turns on the interior lamps for approximately 20 seconds.

Unlock All Doors

When the unlock button on the transmitter is pressed for a second time within 5 seconds of the first press, the BCM receives another signal and supplies battery voltage to the door unlock relay. The door unlock relay applies battery voltage to the right front door lock motor, the left rear door lock motor (sedan only), and the right rear door lock motor (sedan only). At the same time, the BCM turns on the interior lamps for approximately 20 seconds.

Lock All Doors

When the lock button is pressed on the transmitter, the BCM receives a signal and supplies battery voltage to the door lock relay. The door lock relay supplies battery voltage to all of the power door lock motors.

Trunk Lid Release

When the trunk lid release button is pressed on the transmitter, the BCM receives a signal and supplies battery voltage to the Rear Compartment Lid Release Solenoid as long as the vehicle is not in motion.