Can't remember the year right off, but we were in a National Forest campground NW of Trinidad, CO. (45 miles from town and no cell service.)
Got up in the morning to break camp, and to keep the two pups warm, we put them in the pickup and left the engine and heater running. I didn't think that the wife had left her purse in the F150 as well. Dog got up and leaned on the armrest of the door and locked the pickup. When we realized what had happened, we kept coaxing him to step back up on the armrest and hit the lock button again. He always kept missing the switch. I don't remember how long we tried, and he was getting warm and acting like he wanted to lie down and take a nap. (I do that as well when I get good and warm.)
Anyway, I went kind of forward of the pickup to find something to break a window. He saw me go out that way and got his paws back on the armrest, and this time he hit the switch to unlock the doors. I had never seen my family move so fast to get a door open.
59 years of owning automobiles and that was the only "lock-out" that I experienced.