It locks all the doors when I hit a certain speed but when I get out I don't notice because pulling the interior door handle unlocks my door, it just gets frusterateing when I walk around the truck try the door to get my kid out and it is locked so then I have to dig the key back out of my pocket with gloves on and unlock it or walk back around and open the door and hit the unlock switch. Thankfully it won't lock the keys in, only aftermarket alrams and such would do that on my truck and I would yank that junk the day I bought the car.