Car door locks locking even when engine is off

Last month, the doors on our van starting locking on their own repeatedly while driving the car and also when the engine was off. My husband cleaned the battery connections and the problem decreased in freqency but did not go away (the battery tests out OK). The dealer replaced one of the sliding door locks because it would stick on occasion. It seemed to help for about a week and the problem returned. The door locks will lock when the car is parked with the engine off and also when the engine is on. The locks will lock the most when you turn the key in the ignition right before the engine turns over. Tried replacing the batter in the key fob but no effect on the problem. Obviously an electrical problem, but how to fix it?

Honda’s are notorious for this. Maybe Toyota uses the same supplier. The master controller is in the drivers side door and it is the cause of this problem. This is about a $200 repair.

I have a 2011 Toyota Sienna and a 2003 Toyota 4Runner. If I park either vehicle, the doors will automatically lock after a short time interval unless I leave the key in the ignition. I figured that this was the way it was supposed to work so that if an old geezer like me forgets to lock the car, it will be done for him. However, if I leave the key in the ignition, then the doors do not lock. I have an attached garage and I leave the keys in the ignition. If I had a fire in the house, I could get the cars out quickly.

My car also automatically locks within 30 seconds if I don’t lock it myself. However, with the problem I’m having now, the car just keeps locking and locking and locking. It’s intermittent though, it’ll not do it for days and then all of sudden start locking itself when parked in the garage with the engine off.