You have the same fault as me by the sounds of it. Mine is the passenger's door that has problems. If you try to lock it by the button and one of the doors does not lock (driver's door in your case) then all of the locks will unlock again almost instantly. With mine I have tried all sorts of things but in the end I have just pulled the plug on the central locking unit in the passenger's door and lock that one manually. I am unsure as to whether the fault is in the control unit or the lock motor but the car is not worth spending much money on.
Matt
January 2008
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