Interior lights not working?

This might sound stupid but do you have the dome light override switch pressed in. If not perhaps the switch is defective. Here are the interior light wiring diagrams so you can see how the system works. Youc an see the BCM controls the light so I have included the BCM replacement instructions as well. Check out the diagrams (Below). Please let us know what you find.

My interior lights won't go off when the car is on and off. I checked the dimmer switch and the lights still stay on. To prevent my battery from running dead I just take the fuse out. I was wondering do I need a new headlight/dimmer switch?

You can try unplugging dimmer switch and if lights go out then replace it.

I replaced the dimmer switch and its doing the same thing. So what do I check now?

Electrical problem
1995 Chevy Tahoe V8 Four Wheel Drive Automatic

Bought a used 95 tahoe with a whipple supercharger on it. When I test drove it things were fine brought it home washed it then parked it. An hour or so went by got in it to leave noticed that when I stepped on the gas while in drive interior lights came on. Put in reverse stepped on it no lights. Put in neutral revved a little and still no lights. Put back in drive and they came on. Came up to stop sign vehicle acted like it wanted to die picked back up to normal idle. There is also aftermarket alarm.

The only thing that comes to mind after review, is the rear cargo door jamb switch. Theory would support this, as inertial force in drive would act against it, and not any other time. ALLDATA shows me a pretty poor illustration of a pin switch in the RH 'd' pillar, in the cargo door opening. It is shown in the schematic, as a two wire switch, colors purple and black. It looks like you can confirm this as the culprit, by first locating the switch, and then just disconnect it. If it doesn't exhibit the same symptom, you are on the right track. How is the adjustment on the rear door, and can you duplicate it by push/pull or rattling the door?