GM Service Manual Online
For 1990-2009 cars only

Multifunction Alarm Module

The Multifunction Alarm Module controls the automatic door locks.

Door Lock Features

The multifunction alarm module has the following door lock features:

All Door Unlock: The multifunction alarm module unlocks all of the doors when you press UNLOCK on either door lock switch or the remote.

All Door Lock: The multifunction alarm module locks all of the doors when you press LOCK on either door lock switch.

Lockout Prevention: The multifunction alarm module does not lock the doors if you press LOCK on either door lock switch if the key is in the ignition cylinder and the driver door is open.

Remote Driver Door Unlock: The multifunction alarm module locks the driver door when you press UNLOCK on the keyless entry transmitter.

Remote All Door Unlock: The multifunction alarm module unlocks all of the vehicle doors when you press UNLOCK on the keyless entry transmitter again within 4 seconds of pressing unlock.

Remote All Door Lock: The multifunction alarm module locks all of the vehicle doors when you press LOCK on the keyless entry transmitter.

Driver Door All Unlock: The multifunction alarm module unlocks all of the vehicle doors when you turn the key to the UNLOCK position twice in quick succession.

All Door Unlock

The multifunction alarm module unlocks all of the doors when you press UNLOCK once on either the door lock switch or on the keyless remote.

Pressing UNLOCK once on either door lock switch connects ground to the multifunction alarm module through C1 cavity 6. When the circuit is grounded at C1 cavity 6 it activates C1 cavity (8 and 12) to switch from a normally grounded circuit to B+. This supplies power to the actuators and receives ground at the multifunction alarm module C1 cavity 7.

All Door Lock

The multifunction alarm module locks all of the doors when the following actions occur:

    • You press LOCK once on either door lock switch.
    • All of the doors are closed.

The multifunction alarm module does not lock the doors when the following conditions exist:

    • The driver door is open.
    • The key is fully inserted in the ignition switch.

The above conditions enable the lockout prevention feature.

Lockout Prevention

The multifunction alarm module does not lock the vehicle doors when you press LOCK on either door lock switch with the lockout prevention feature active. The multifunction alarm module activates the lockout prevention feature when the following conditions exist:

    • A vehicle door is open.
        An open vehicle door causes a ground signal in Junction Block 2 C4 cavity 7.
    • The key is fully inserted in the ignition switch cylinder.
        Full insertion of the key causes a ground signal in C2 cavity 4.

The multifunction alarm module disables the following automatic door lock features:

    • All door lock
    • Last door closed locking
    • Keyless entry system unlock