Slightly different "problem" here. In mine, the rear hatch locks itself if I'm sat waiting in the car for my wife to come back from the shops. Even though the car is open, with me in it, listening to the radio with the key in the first (aux) position, she will be unable to open the tailgate until I open the drivers door. Then the lock works and she can open it to put her stuff in. I obviously can't check this, because as soon as I open the door to get out, the lock would be working. Is this some kind of safety feature fitted to modern cars, because my Picasso was exactly the same. All I can say is it's a pain in the A**E and I'd dearly love to know if there's any way to disable it.
2008 2.0 TDCi Zetec