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For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2000 🢒 Montana 🢒 Body and Accessories 🢒 Doors 🢒 Power Door Locks Operation

Automatic Door Lock Features

The body control module (BCM) controls the door locks. One of three BCM types is installed on this vehicle based on vehicle equipment:

    • BCM type 2 provides power door locks, plus interior illumination control, inadvertent load (battery rundown) protection, and chime functions.
    • BCM type 3 provides BCM type 2 features plus the keyless entry system (RPO AU0).
    • BCM type 4 provides BCM type 2 and 3 features plus the content theft deterrent system (RPO UA6) with remote activation verification and remote alarm.

The BCM type 2 has these door lock features:

    • All door unlock: The BCM unlocks all doors when pressing unlock on either door lock switch.
    • All door lock: The BCM locks all doors when pressing lock on either door lock switch.
    • Last door closed locking: When pressing lock on either door lock switch with the ignition switch in the LOCK or OFF position, the BCM locks all doors five seconds after closing all vehicle doors. Refer to Automatic Door Lock System Description .
    • Lockout prevention: When pressing lock on either door lock switch with the key in the ignition cylinder and the driver's door is open, the BCM does not lock the doors. Refer to Automatic Door Lock System Description .
    • Lockout prevention override: When pressing and holding lock on the LF door lock switch for at least three seconds, the BCM overrides the lockout prevention thus locking all doors. Refer to Automatic Door Lock System Description .
    • Ignition OFF unlock: When turning the ignition switch from RUN to OFF, the BCM unlocks all vehicle doors. Refer to Automatic Door Lock System Description .
    • Shift into PARK unlock: When shifting the transaxle into PARK, the BCM unlocks all vehicle doors. Refer to Automatic Door Lock System Description .
    • Shift out of PARK lock: When shifting the transaxle out of PARK with the driver's door closed, the BCM locks all vehicle doors. Refer to Automatic Door Lock System Description .
    • Sliding door delayed locking: The BCM locks all doors three seconds after closing sliding door(s).

The BCM type 3 (RPO AU0) has these door lock features (in addition to BCM type 2 features):

    • Remote driver door unlock: The BCM unlocks the driver's door when pressing unlock on the keyless entry transmitter.
    • Remote all door unlock: The BCM unlocks all vehicle doors when pressing unlock on the keyless entry transmitter again within five seconds of pressing unlock.
    • Remote all door lock: The BCM locks all vehicle doors when pressing lock on the keyless entry transmitter.

The BCM type 4 (RPO UA6) has this door lock feature (in addition to BCM type 2 and 3 features):

    • Key cylinder unlock: When unlocking a door by using the LF, RF or liftgate door key cylinder, the BCM unlocks all vehicle doors while holding the key in the unlock position for one second.
    • Key cylinder lock: When locking a door by using the LF, RF or liftgate door key cylinder, the BCM locks all vehicle doors while holding the key in the lock position for one second.

For more information regarding the keyless entry system refer to Keyless Entry System Circuit Description in Keyless Entry.

For more information regarding the theft deterrent system refer to Content Theft Deterrent (CTD) Circuit Description in Theft Deterrent .

For more information regarding the body control system refer to Body Control System Circuit Description in Body Control System.

All Door Unlock

The BCM unlocks all doors when pressing unlock once on either door lock switch. Note: the BCM does not unlock the doors when the content theft deterrent system (RPO UA6) is armed.

All Door Lock
    • The BCM locks all doors when pressing lock once on either door lock switch with all doors closed.
    • The BCM delays door locking when the driver's door is open with the key removed from the ignition switch, thus enabling the last door closed locking feature if the locking control mode is in mode 3 or 4. A first press of lock on a door lock switch initiates this feature. This causes the BCM to sound the chime 3 times, indicating last door closed locking is active. Five seconds after all doors are closed, the BCM locks all doors. Pressing lock twice on a door lock switch bypasses the last door closed locking feature, thus the BCM locks all doors immediately with a door still open.
    • The BCM does not lock the doors when the driver's door is open and the key is fully inserted in the ignition switch, thus enabling the lockout prevention feature.

Sliding Door Delayed Locking

The BCM initiates the sliding door delay locking feature when pressing lock on either door lock with a sliding door open, on one of these conditions is met:

    • The ignition switch in ACC or RUN position.
    • The ignition switch in LOCK or OFF position and the last door closed locking feature is disabled. Refer to Automatic Door Lock System Description .
    • The ignition switch in LOCK or OFF position and the lockout prevention override feature is enabled. Refer to Automatic Door Lock System Description .

In addition, the BCM initiates the sliding door delay locking feature when the shift out of PARK lock feature is active with a sliding door open.

When the sliding door delayed locking feature is initiated (see criteria above), the BCM locks all doors three seconds after closing sliding door(s).

Sliding Door Delayed Locking Override

The BCM locks all doors when pressing lock on either door lock switch or keyless entry transmitter during the three second delay period. This action overrides the sliding door delay locking feature. However, the BCM will not lock doors if the lockout prevention is active. Refer to Automatic Door Lock System Description .

If a sliding door was open at the time the BCM locks all doors (override feature activated), the BCM initiates the sliding door delay locking feature after closing sliding door(s).

Sliding Door Delayed Locking Cancellation

The BCM cancels the sliding door delay locking feature when pressing unlock on either door lock switch or keyless entry transmitter.

When opening a sliding door during the three second delay period, the BCM cancels the sliding door delay locking feature and waits for sliding door(s) to close again. When closing sliding door(s), the BCM re-initiates the sliding door delay locking feature.

Key Cylinder Unlock (RPO UA6)

When using the LF, RF or liftgate door key cylinder, the BCM unlocks all vehicle doors while holding the key in the unlock position for 1 second.

Key Cylinder Lock (RPO UA6)

When using the LF, RF or liftgate door key cylinder, the BCM locks all vehicle doors while holding the key in the lock position for 1 second.

Courtesy Lights

Illuminated Entry

The BCM turns on the courtesy lights when unlocking the LF, RF, or liftgate door using door cylinder lock (BCM type 4 only). Refer to Interior Lights Circuit Description for more information.

Delayed Illumination

The delayed illumination feature is canceled when pressing lock on a door lock switch or a keyless entry transmitter. Refer to Interior Lights Circuit Description for more information.