Inside light come on by themselves

I have a 2000 Mercury Grand Marquis. Lately I noticed that the inside lights come on and can stay on from 1-20 minutes, never predictable which sometimes drains the battery so the car doesn’t start but not always. I have no idea what can cause this. Please tell me if you have any idea, what can cause this and how I can repair it.

Thank you.

One of the door switches may be making intermittent contact and cleaning the switch may help fix this trouble. The switch may be part of the door latch inside the door. I know Ford trucks in the those years had this same problem.

My 98 Windstar had the switches inside the door latch. I cleaned the switch contacts by spraying CRC Electrical Contact Cleaner or WD40 into the door latch while working the door handle.

Ed B.