I just found this one in the fall. I would hop in the truck stick the key in and start the engine and from time to time the electric locks would lock. Truck would run fine no hickup on lag or bog in starting. As it got cooler I noticed it more often. I checked fuses etc nothing showed. I thought about the way the locks work, change voltage polarity to lock vs unlock, and start to think maybe the battery was just weak enough that a spike was being sent through the system. Nothing else (except lights) operate during startup.

What do you know, I take the trcuk down and run a battery load test and it fails. Replaced the battery and I have not had the phantom lockup since...........

So, if you doors lock on start up check the battery and replace.