Interior lights--2002 Buick Rendezvous

The interior lights in this car seem to have a mind of their own. They do not react to opening and closing doors, and I have had to manually set the light switch to off to keep from draining the battery. Of course, this is inconvenient at night. There is no visible switch like in the old days, and the lights ignore all four doors–five counting the lift-back. Any ideas on what I should be looking for?

“They do not react”… In what way? Stay on constantly or off?

Your dealers OBD2 scan tool (GM tech 2) has the ability to tell you the status (open or closed) of the switches that control your interior lighting. If you dont like using a dealer find a independent that has a scan tool with this ability. Diagnostic equipment like the Tech2 really drop the time required to find the cause of such concerns. Last time I heard a price on a GM Tech2 it was $1800.00. Do any of the other scan tools (which are probably cheaper) have this ability. You coul diag. the old way,but the time (money)issue.

No reaction at all. If I set the switch to on, they come on. If I then set the switch to door, they stay on regardless of opening or closing doors. If I turn the switch to off, they go off, and again ignore door changes if I move the switch to door. In other words, the door setting on this dashboard-mounted switch is useless.

Looking at some data for your model it looks to that the light switch has a DOME light position and that appears to be working from what you say, along with the OFF position. The switch makes a ground connection when the position of the switch is selected and it ties to the Body Control Module. There are door switches also that make a ground when the doors are opened. They tie to A2, A7, A10, and B1 of the BCM. You could manually tie one of those leads to ground and see if the light comes on. If it doesn’t then the BCM may be at fault. That would be expensive to replace.

Well, I got it, but not the way I would have anticipated. The A/C recently died, and the diagnosis was a bad Body Control Module ($529 Parts and Labor). Now the lights work properly. I wonder what else might have been not right due to that part failure. Oh well. Thanks for the replies.

Glad you got it fixed and thanks for the feedback on fix for this. Sometimes the cure is not cheap to do.