I have a 2oo3 MC 3.8l v6 with 92, oo0 miles. All the interior lights ( Dash, climate control, radio, and window/door lock switches) are not working with the exception of the Onstar system, and Dome lights. All the Instruments still function but will not light at night. Ive' checked every fuse I could find. Someone suggested it may be a sensor, but I don't know where to look. I figured if it was a sensor of such, my headlights would operate on it, but they work properly also. What could be the problem, and how is it fixed?