GM Service Manual Online
For 1990-2009 cars only

Key-In Warning Alarm Circuit Description

The key-in warning alarm will sound if the following conditions occur simultaneously:

    • The ignition key must be in the ignition switch
    • The right hand (RH) front door is open.

When the ignition key is in the ignition switch and the RH front door is open, the ignition key alarm switch closes. The RH door jamb switch also closes. When both of the switches close, the Body Control Module (BCM) senses ground. When the BCM senses ground the key-in warning alarm activates. The key-in warning alarm will stop sounding if 1 of the following conditions occurs:

    • Removal of the ignition key from the ignition switch
    • Closing the RH front door

Fasten Safety Belts Warning Alarm Circuit Description

The fasten safety belts warning alarm will sound when the following conditions occur simultaneously:

  1. The ignition switch is in 1 of the following positions:
  2. • RUN
    • BULB TEST
    • START
  3. The right hand (RH) front safety belt is not fastened.

The BCM senses ground when the RH front safety belt is not fastened. The alarm will sound for approximately 5 seconds. The inflatable restraint sensing diagnostic module also senses ground when the RH front safety belt remains unbuckled. Refer to SIR in Restraints for more information.

The BCM also incorporates an indicator within the instrument cluster. The fasten safety belts indicator works in conjunction with the fasten safety belts warning alarm. When the audio BCM receives a signal that the RH front safety belt is unfastened, the BCM turns the fasten safety belts indicator ON>

Lamps-On Warning Alarm Circuit Description

The lamps-on warning alarm will sound of the following conditions occur simultaneously:

    • The headlamp switch is in the HEAD or the PARK position.
    • The panel dimmer switch is not in the fully dim position.
    • The ignition switch is in 1 of the following positions:
      • LOCK
      • ACC
      • OFF

When the headlamp switch is in the HEAD or the PARK position, voltage applies through the ILLUM FUSE 12 to the BCM. When the lamps ON input terminal of the BCM senses voltage and there is an absence of voltage at the ignition ON input terminal, the lamps-on warning alarm will sound. You can silence the lamps-on warning alarm by either turning the headlamp switch to the OFF position or turning the ignition switch to the RUN position.