1998 GMC Savana Van Owner's Manual - Page 115

Interior Lamps Dome Lamps The dome lamps will come on when you open the doors. You can also turn the dome lamps on by rotating the thumbwheel, located next to the headlamp knob, all the way up to the second notch. In this position, the dome lamps will remain on whether the doors are open or closed. To use the dome override feature, push the button into the "in" position. With the button in this position, the dome lamps will remain off when the doors are open. To return the lamps to automatic operation, push the button and return it to the "out" position. With the button in this position, the dome lamps will come on when you open the doors. Reading Lamps (Option) I You can use the DOME OVERRIDE button, located below the headlamp knob, to set the dome lamps to automatically come on when the doors are open, or to remain off. If your vehicle has reading lamps, press the button next to the lamp to turn the lamp on. Press the button again to turn thelamp off. 2-43