Didn't think this was possible...
 

I was at a party last night, started my truck with the keys in the ignition, sitting in the seat getting ready to leave, then I saw someone I wanted to say hello to and left the truck running with the keys in it, when I came back maybe some 15 min later all the doors were locked. So today I tried to lock the keys in my truck with the keys in the ignition and the only way I could do that was with the spare key fob. It’s a 2011 GMC Sierra 1500 with keyless entry and remote start. Any ideas how this could have happened?

That shouldn't have happened at all...

The one time I accidentally bumped my lock button getting out it beeped and yelled at me until I hit the unlock button and refused to lock..

How did you end up getting in?

Well my Uncle was there and he took me to my house to get the other key fob, which I was only about 8 miles away. But what is strange is that the next day I tried to lock myself out of it and the only way I could do that was using the extra key fob.

With the truck running, key on, engine running, vehicle in park, the truck will resist all efforts to lock the door using the power locks. Key fob, door switch, whatever. But if you manually push the lock knob down on your way out on accident, then it will stay locked and you'll be boned.

I remember way back in high school a Jimmy Johns driver pulled up in the bus lane about a half hour before school let out and left it running and accidentally locked the keys in the car...

He was freaking out and it took over an hour for someone to come with a break in kit... but by then, he had run out of fuel.

The worst part... it was a Volkswagen Rabbit Diesel... he ended up having to get it towed and bled out

Your right, but for that to happen you would have to manually hit the electric door lock button, this would lock all the doors < crew cab, you then can't open your door with the handle so you have to reach behind you and pull up on the door knob to open only your door, then when getting out you would have to manually push down the lock knob again. Thats 3 steps by accident.

I've had the electric door locks lock on both my 2004 GMC Z71 and my wife's 1998 Acura. The engine was not running at the time on either. It's only happened a couple of times. Now if I get out of the vehicle with the key in the ignition I always roll down the drivers window, just in case.

Strange how knob is censored.

I've been there too. You get that long long wait after a phone call for your extra keys. You wouldn't believe how irritating it is when you ask someone if they have an extra key and they look at you with a blank stare.