GM Service Manual Online
For 1990-2009 cars only

The reading lamps are located on the overhead console on the headliner and in the rear door opening. These lamps come on automatically when any door is opened and it is dark outside.

For manual operation, press the button to turn them on. Press it again to turn them off.

If the reading lamps are left on, they automatically shut off 10 minutes after the ignition has been turned off.