Multi-Function Alarm Module - Additional Functions
90buick08Builetin : 90-9-3
Date : June, '90
Ref. No. : 90-141-9
Corp. Ref. No.: 078109
SUBJECT: MULTI-FUNCTION ALARM MODULE - ILLUMINATED ENTRY SYSTEM OPERATION INFORMATION
MODELS AFFECTED: 1990 SKYLARK
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 retractor 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 112 second after the door is closed. The 112 second delay is provided by the multi-function alarm module. As part of the system operation, a two minute "time out" is activated to prevent reactivation of the system. At the end of the "time out" period, the interior lamps will flash briefly as the module resets this interior timer.
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 de-energize 112 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.