GM Service Manual Online
For 1990-2009 cars only

The audible warning system is controlled by the audio alarm module on base models, or the body control module (BCM) on luxury models. On base models the chimed output is produced by the audio alarm module. On luxury models the chimed output is produced within the BCM. Power is provided to either system from the GAUGES fuse through CKT 39 (PNK). Ground is provided through CKT 150 (BLK) to G200 for either module.

Fasten Safety Belts Warning

The fasten safety belts warning chime sounds and the instrument cluster indicator lights when the ignition switch is in the RUN, BULB TEST, or START position with the left front safety belt not fastened. When this condition occurs, the left front seat belt switch will close and provide a ground to G202. Either the body control module or the audio alarm module also provide an output to the instrument cluster safety belt lamp through CKT 234 (YEL). The fasten safety belts chime will sound for 8 seconds when ignition voltage is applied and the left front seat belt is not fastened. The fasten safety belts warning indicator will light constant for the first 15 seconds and then flash for another 60 seconds. If the seat belt is fastened within the initial 8 seconds, the chime will still cycle for the remainder of the 8 seconds.

Key-In Warning Alarm

The key-in warning alarm chime will sound if the key is in the ignition and the left front door is opened. When this condition occurs, the key-in warning buzzer switch and the left front door jamb switch will be in a closed position providing a ground path for either the BCM or the audio alarm module to G200 through CKT 150 (BLK). The key-in warning alarm chime will stop sounding if one of the following conditions occur:

    • Removing the key from the ignition.
    • Closing the left front door.

Lights On Warning Alarm

On luxury models the lights on warning alarm chime will sound when the headlamp and panel dimmer switch is in the HEAD or PARK position, the ignition is in the OFF position and the left front door is opened. When the left front door is opened ground is provided to the BCM through the left front door jamb switch to G200 through CKT 150 (BLK). The chime will sound until the headlamp and panel dimmer switch is placed in the off position or the left front door is closed.

On base models the lights on warning alarm chime will sound when the headlamp and panel dimmer switch is in the PARK or HEAD position and the ignition switch is placed in the off position. Voltage is supplied to the audio alarm module lights on chime function through the ILLUM fuse through CKT 8 (GRY). Module ground is provided through CKT 150 (BLK) to G200. The chime will sound until the ignition is placed in the RUN position or the headlamp and panel dimmer switch is placed in the off position.

Overspeed Warning Alarm

The overspeed warning alarm is only provided on export vehicles. The overspeed alarm chime will sound when the vehicle speed exceeds 75 mph (120 kmh). This speed is not adjustable and is based on a frequency provided from the vehicle control module (VCM) through CKT 389 (DK GRN). The instrument cluster also receives a signal input for speedometer/odometer functions.