GM Service Manual Online
For 1990-2009 cars only

The keyless entry system is a supplementary vehicle entry device. Use the keyless entry system in conjunction with a door lock key. Radio frequencies or discharged batteries may disable the system.

Keyless entry allows you to operate the following components:

    • The door locks
    • The rear lift glass release
    • The illuminated entry lamps
    • The panic alarm (instant alarm)

The keyless entry system has the following main components:

    • The transmitters
    • The remote control door lock receiver (RCDLR)

The RCDLR communicates with the body control module through the keyless entry serial data circuit. When you press a button on a transmitter, the transmitter sends a signal to the RCDLR. The RCDLR interprets the signal and sends a request over the keyless entry serial data circuit to the BCM. The BCM performs the appropriate function depending on which button on the transmitter is depressed.

Keyless Entry Functions (Mode 1)

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

    • Unlock all of the doors.
    • Illuminate the interior lamps for approximately 40 seconds or until the ignition is turned ON.
    • 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 radio/entertainment settings for that driver.

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

    • Lock all of the doors.
    • Immediately turn off the interior lamps.
    • Flash the exterior lights (if selected ON in personalization).
    • Arm the content theft deterrent (CTD) system.

Press the LOCK button a second time in order to chirp the horn (if selected ON in personalization).

Keyless Entry Functions (Mode 2)

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

    • Unlock the driver door.
    • Illuminate the interior lamps for approximately 40 seconds or until the ignition is turned ON.
    • 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 radio/entertainment settings for that driver.

Momentarily press the UNLOCK button a second time in order to unlock the remaining doors.

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

    • Lock all of the doors.
    • Immediately turn off the interior lamps.
    • Flash the exterior lights (if selected ON in personalization).
    • Arm the content theft deterrent (CTD) system.

Press the LOCK button a second time in order to chirp the horn (if selected ON in personalization).

Rear Compartment Lid Release

If the vehicle transaxle is in PARK or NEUTRAL and the ignition is in the OFF position, a single press of the rear lift glass release button will open the rear lift glass.

Alarm

A single press of the panic button performs the following functions:

    • Illuminates the interior lamps.
    • Pulses the horn.
    • Flashes the head lamps for 2 minutes or until the following conditions occur:
       - The panic button is pressed again.
       - The ignition switch is turned to the RUN position with a valid key.

Keyless Entry Personalization

The keyless entry unlock function and the remote activation verification (exterior lamps and horn chirp) may be personalized for two different drivers. 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 RCDLR are synchronized to the appropriate order. If a programmed transmitter sends a signal that is not in the order that the RCDLR 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.

Keyless Entry Indicator(s)

Key Fob Battery Low Indicator

When the voltage of the keyless entry transmitter (key fob) battery falls below 2.2 volts, the transmitter sends a low battery signal to the remote control door lock receiver (RCDLR). The low battery signal is sent every time the transmitter is used for any remote keyless function. The RCDLR communicates the low battery messages to the body control module (BCM). When the BCM receives three consecutive low battery messages from the RCDLR, the BCM sends a class 2 message to the instrument panel cluster (IPC). The IPC illuminates the key fob battery low indicator in the message center whenever the ignition is ON. The indicator remains illuminated until a transmitter with a good battery (2.2 volts or greater) is used to perform any remote function. When the indicator is illuminated and a transmitter with a weak battery is used to perform any remote function, the indicator turns off for approximately 2 seconds and then turns back on.