MULTI-FUNCTION ALARM MODULE ILLUMINATED ENTRY SYSTEM

Model and Year: 1990 J CARS

The multi-function alarm module has two additional functions for the 1990 model year. They are as follows:

1. Control of the illuminated entry system

2. Control of the lap and shoulder safety belt retainer solenoids

When either front door is opened, the corresponding door handle switch closes. This pulls the voltage on the circuit low and signals the multi-function alarm module that the door is open. The multi-function alarm module turns on the interior lamps by completing the circuit to ground for the interior lamps. If the door is closed within 40 seconds of opening, the interior lamps will remain on until the ignition lock cylinder is rotated to the "RUN" position or until 40 seconds (from door opening) has elapsed, which ever occurs first. If either front door is open for longer than 40 seconds, the interior lamps will remain on for as long as the door is open and will turn off 1/2 second after the door is closed. The 1/2 second delay is provided by the multi-function alarm module.

The vehicle no longer has a door jam switch on either of the front doors. However, if the vehicle is a 4-door model, the rear doors do operate a door jam switch which turns on the interior lamps in the conventional manner.

When either of the front doors is opened, the multi-function alarm module also completes a circuit to ground to energize the two lap belt retractor solenoids and the two shoulder harness retractor solenoids. These four solenoids remain activated to hold the retractor pendulums in the release position so that the motion of opening and closing the front doors is not impeded by the retractors. Like the interior lamps, the retractor solenoids remain energized for as long as either front door is opened and will deenergize 1/2 second after the door is closed.

Since all four retractor solenoids are energized when either front door is open and the interior lamps are turned on, it is a good practice not to leave a front door open for an extended period.

Because the multi-function alarm module does have additional functions, complete understanding of these functions are required to prevent misdiagnosis and/or premature replacement of the multi-function alarm module.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.