GM Service Manual Online
For 1990-2009 cars only

A reminder chime will sound when your headlamps or parking lamps are manually turned on, the driver's door is opened and your ignition is in OFF, LOCK, or ACCESSORY. To turn the chime off, turn the control counterclockwise or turn the instrument panel brightness thumbwheel down to the fully dimmed position. In the automatic mode, the headlamps turn off once the ignition key is in OFF.