I have had this problem for a couple years but I finally decided to get on Chevy forum since I am having other problem with my 1994 Chevy K1500. I can't turn my dome light off. I even unhooked the switch. Some how it is getting power. The only way to turn it off it to pull the bulb out. Any ideas?

 

There is a switch in the dash that dims the gauge cluster lights and also turns on the dome light when you turn it all the way in one direction. This switch could be stuck in the on position.

 

That is a 'ground searching' circuit.

Power is always there and the circuit is looking for ground, usually at the door jab switches or at the headlight switch.

Allan