GM Service Manual Online
For 1990-2009 cars only

The dome lamp has three positions.

ON: In this position, the dome lamp is always on.

DOOR: In this position, the light automatically comes on when a door is opened. It will turn off 30 seconds after the last door is closed. If the ignition is turned on, the light turns off immediately unless a door is open.

OFF: In this position, the dome lamp is always off, even when a door is opened.

The dome lamp can be set to remain on for a preset amount of time after the ignition has been turned off. See Vehicle Personalization .