GM Service Manual Online
For 1990-2009 cars only

The keyless entry system is a supplementary vehicle entry device. Radio frequencies or discharged batteries may disable the system.

Keyless entry allows you to operate the following components:

    • The door locks
    • The rear compartment lid release
    • The illuminated entry lamps
    • The panic alarm/instant alarm

The keyless entry system has the following main components:

    • The transmitters
    • The Liftgate Module (LGM)

When you press a button on a transmitter, the transmitter sends a signal to the Liftgate Module. The module interprets the signal and activates the requested function via a class 2 message over the serial data line.

Unlock Driver's Door Only

Momentarily press the UNLOCK button in order to perform the following functions:

    • Unlock the driver door only.
    • Turn the interior lamps on for a predetermined amount of time or until the ignition is turned to the RUN position with a valid key.
    • Flash the exterior lights, if selected ON in personalization.
    • Disarm the content theft deterrent (CTD) system (if equipped).
    • Deactivate the CTD system when in the Alarm Mode, if equipped.
    • Recall the memory seat and memory mirror positions for that driver.

Unlock All Doors-Second Operation

Momentarily press the UNLOCK button a second time (within 2 seconds of the first press) in order to perform the following functions:

    • Unlock the remaining doors.
    • Illuminate the interior lamps for a predetermined amount of time or until the ignition is turned to the RUN position with a valid key.
    • Flash the exterior lights, if selected ON in personalization.
    • Chirp the horn, if selected ON in personalization.
    • Recall the memory seat and memory mirror positions for that driver.

Lock All Doors

Press the LOCK button in order to perform the following functions:

    • Lock all of the doors.
    • Momentarily illuminate the interior lamps.
    • Flash the exterior lights, if selected ON in personalization.
    • Chirp the horn, if selected ON in personalization.
    • Arm the content theft deterrent (CTD) system.

Rear Compartment Lid Release

If the vehicle transaxle is in PARK and the ignition is in the OFF position, a single press of the rear compartment release button will open the rear compartment lid. The interior lamps will not illuminate.

Panic Alarm

A single press of the transmitter panic button will:

    • Pulses the horn.
    • Illuminates the interior lamps.
    • Flash the parking lamps.
    • Flash the headlamps .

All of the above will occur for a predetermined amount of time or until:

    • The Panic button on the transmitter is pressed again.
    • The vehicle is unlocked with the key.
    • The ignition switch is turned to the RUN position with a valid key

Keyless Entry Personalization

The exterior lamps and horn chirp may be personalized for 2 separate drivers as part of remote activation verification. For mode descriptions and programming instructions, refer to Driver Personalization in Personalization.

Rolling Code

The keyless entry system uses rolling code technology. Rolling code technology prevents anyone from recording the message sent from the transmitter and using the message in order to gain entry to the vehicle. The term "rolling code" refers to the way that the keyless entry system sends and receives the signals. The transmitter sends the signal in a different order each time. The transmitter and the Liftgate Module (LGM) are synchronized to the appropriate order. If a programmed transmitter sends a signal that is not in the order that the LGM expects, then the transmitter is out of synchronization. This occurs after 256 presses of any transmitter button when it is out of range of the vehicle.

Automatic Synchronization

The keyless entry transmitters do not require a manual synchronization procedure. If needed, the transmitters automatically resynchronize when any button on the transmitter is pressed within range of the vehicle. The transmitter will operate normally after the automatic synchronization.