1998 GMC Sonoma Owner's Manual - Page 106

Exit Lighting With exit lighting, the interior lamps will come on when you remove the key from the ignition to help you see while exiting the vehicle. These lights will stay on for a short period of time and then will go out. Dome Lamps The dome lamps will come on when you open the doors. You can also turn the dome lamps on by rotating the thumb wheel, located next to the parking/headlamps knob, all the way up to the top detent position. In this position, the dome lamps will remain on whether the doors are opened or closed. You can use the DOME OVERRIDE button, located below the parking/headlamp knob, to set the dome lamps to come on automatically when the doors are opened, or to remain off. To turn the lamps off, press the button once. With the button in this position, the dome lamps will remain off when the doors are open. To return the lamps to automatic operation, press the button again and return it to the "out" position. With the button in this position, the dome lamps will come on when you open the door. This will not override the illuminated entry feature. Illuminated Entry Your vehicle is equipped with an illuminated entry feature. When the doors are opened,the dome lamps will come on if the DOME OVERRIDE button is out. When all the doors are closed, o r the dome lamp button is pressed in, the lamps will stay on for a short period of time and will then go out. Front Map Lamps(If Equipped) If your vehicle has optional front map lamps, they are located on the inside rearview mirror. They will automatically come on for approximately 40 seconds when the doors are unlocked withthe keyless entry transmitter (if equipped) or until the ignition key is turnedto RUN or ACCESSORY. The lamps will also stay on for approximately 40 seconds after you exit the vehicle unless you lock the doors with the keyless entry transmitter. You can also turn the lamps on and off by pmsing the switch near each lamp. 2-42