This seems to be a mechanical problem, probably because so much is made with plastic crap. I have had this problem from the first cold snap and every summer. The worst is that is happens and then when the temperature changes, they unlock. The automatic locking at 5 miles per hour makes it impossible to avoid locking the doors when your driving and unless you leave your car open to any vandle and thief you cannot avoid parking and leaving the car unlocked... I find it hard to believe this is the only car with this problem since all four doors have the problem! I love the odd looks I get from the dealer like they never heard of this before - growl to the nth power!