electric door locks went random on T&C 2001

Earlier this week I was sitting in my T&C when all of the sudden the door locks started opening and closing by themselves. I started the van and it continued until I turned off the car. About 15 min's later I started the van and it started again, about 2-3 times a minute, as I drove back to my shop. I parked the van and went inside and I could hear the looks going of this time only locking the doors. I took the van to my mechanic and by the time they had a chance to look at it, it had quit and is working normally. There where no remote fobs in the car at the time and I had covered too much area for it to be a hacker messing with me. Neither my mechanic, nor the dealership, have seen this happen. Does anybody have any ideas? Thanks