GM Service Manual Online
For 1990-2009 cars only

The keyless entry system allows the driver to complete the following functions from outside the vehicle by using a hand-held radio transmitter:

    • Unlock the door locks. The interior courtesy lamps activate automatically when using this function.
    • Lock the door locks.
    • Operate the power sliding door, if equipped.
    • Operate the remote alarm. This feature is available only on vehicles equipped with the content theft deterrent (RPO UA6).

The transmitter operates in the UHF band. The transmitter sends digitally-coded signals to the remote control door lock receiver (RCDLR) when you press any of the transmitter buttons.

The RCDLR detects and decodes the transmitter signals. For locking, unlocking, and remote alarm commands, the RCDLR sends command messages to the body control module (BCM). These messages serve to operate the following functions:

    • The door locks actuators
    • The interior courtesy lamps
    • The remote alarm

For power sliding door open/close operations, the RCDLR sends a direct signal to the power sliding door control module. Refer to Power Sliding Door (PSD) Operation in Doors.

You can also operate the power sliding door features manually:

    • The power sliding door
    • The door locks
    • The interior courtesy lamps

For example, the door locks respond to the power door lock switches.

You can program the keyless entry system with a maximum of 4 keyless entry transmitters.

Body Control Module (BCM)

The body control module (BCM) controls the door locking and the interior lighting portions of the keyless entry system. On vehicles equipped with the content theft deterrent system (RPO UA6), the BCM also controls the remote alarm. One of 3 BCM types is installed on this vehicle based on vehicle equipment:

    • BCM type 2 provides the following features:
       - Interior illumination control
       - Inadvertent load (battery rundown) protection
       - Chime functions
       - Automatic power door locks
    • BCM type 3 provides the following features:
       - BCM type 2 features
       - Keyless entry system (RPO AUO)
    • BCM type 4 provides the following features:
       - BCM type 3 features
       - Content theft deterrent system (RPO UA6) with remote activation verification and remote alarm

Refer to Body Control System Circuit Description in Body Control Systems.

Diagnostic Trouble Codes (DTC)

The remote control door lock receiver (RCDLR) sends the following messages to the body control module (BCM) through the RFA link.

    • Door locking commands
    • Remote alarm system, if equipped

The BCM sets DTC 8 if the RFA link circuit 377 is open or shorted to B+ or ground.

Keyless Entry Functions

Remote driver door unlock: The driver door unlocks when you press the UNLOCK button on the keyless entry transmitter.

Remote all-door unlock: If in mode 1 all of the doors unlock when you press the UNLOCK button on the keyless entry transmitter. If in mode 2, all of the doors unlock when you press twice (or more) on the UNLOCK button on the keyless entry transmitter. Refer to Remote Unlock Control Customization .

Remote all-door lock: All doors of the lock when you press the LOCK button on the keyless entry transmitter.

Power sliding door open/close function: The power sliding door opens when you press the power sliding door OPEN/CLOSE button on the keyless entry transmitter.

Vehicles equipped with the content theft deterrent system (RPO UA6) have the following additional features:

Remote activation verification: The exterior lamps flash and/or the horn sounds when you use the keyless entry transmitter. Refer to Remote Activation Verification (RAV) Customization .

Remote alarm: The exterior lights flash and the horn sounds alternately for 2 minutes when you press the alarm button on the keyless entry transmitter. Pressing the alarm button again within 2 minutes stops the remote alarm.

Remote Driver Door Unlock

When you enable the remote driver door unlock feature (mode 2) through feature customization, the RCDLR sends a message to the BCM through circuit 1455. This message unlocks the driver door when you press once on the UNLOCK button on the keyless entry transmitter.

When you disable the remote driver door unlock feature (mode 1) through feature customization, the RCDLR sends a message to the BCM through circuit 1455. This message unlocks all of the doors when you press once on the UNLOCK button on the keyless entry transmitter.

Refer to Remote Unlock Control Customization .

Remote All Door Unlock

When you disable the remote driver door unlock feature (mode 1) through feature customization, the RCDLR sends a message to the BCM through circuit 1455. This message unlocks all doors when you press once on the UNLOCK button on the keyless entry transmitter.

When you enable the remote driver door unlock feature (mode 2) through feature customization, the RCDLR sends a message to the BCM through circuit 1455. This message unlocks all doors when you press twice within 5 seconds on the UNLOCK button on the keyless entry transmitter.

Refer to Remote Unlock Control Customization .

Remote All Door Lock

The RCDLR sends a message to the BCM through circuit 1455. This message locks all of the doors when you press once on the LOCK button on the keyless entry transmitter. However the automatic door locks control the door-locking procedure as follows:

    • The BCM will not lock the doors when the lockout prevention feature is active.
    • The BCM delays door locking when the last-door-closed locking feature is active.

Refer to Automatic Door Lock System Description .

Remote Alarm

Vehicles equipped with the content theft deterrent system (RPO UA6) have a remote alarm feature. When you press the ALARM button on the keyless entry transmitter, the RCDLR sends a message to the BCM through circuit 1455. This message performs the following 2 functions alternately for 2 minutes:

    • Flash the exterior lamps
    • Sound the horn

In order to stop the alarm, press the ALARM button again.

Power Sliding Door Open/Close Function

When you press the power sliding door OPEN/CLOSE button on the keyless entry transmitter, the remote control door lock receiver (RCDLR) grounds circuit 1894 momentarily. This action sends a ground signal to the power sliding door control module which operates the power sliding door.

Interior Courtesy Lamps Activation

The BCM turns ON the interior courtesy lamps when you unlock the doors using the keyless entry transmitter. Refer to Interior Lights Circuit Description in Lighting Systems.