.... why do my reverse lights keep coming on when my van isn't even on? In particular after getting out and locking the door, they're on. I've noticed several GM vehicles doing this in parking lots (which is incredibly annoying - sitting around and waiting for a vehicle to reverse which doesn't even have occupants)... and I certainly don't want to contribute to the problem.... so how do I fix my van?

 

Well my wife's truck and my car are not GMs though upon exiting after dusk or in a dim garage our headlights stay on and the lights on the bottom of the side view mirrors and doors stay on for about 30 seconds. My Express does not have that entry/exit lighting option which you must have.

 

Its the sentry/valet system. Its meant to light your way to and from the car.
I hate it too sometimes as i worry its not going to shut off. Also, it should quit once the alarm is set since that can be done from a distance....but doesn't.