So my friends 2007 Golf City driver side door won’t lock with either door lock switch or fob. Car has central locking so all doors lock at once from the fob. Only driver door doesn’t lock and button has to be pushed down or key manual lock. Using the fob will successfully unlock the door. Where should I start looking? The actuator seems to be functioning at least to unlock, is it possible it is still faulty?
If were to take an educated guess. I would say that the unlocking and locking process is divided into 2 separate circuits with 2 different solenoids and relays. Looking in your owner's manual in the section mentioning the fuses might give you a clue what is going on.
Another possibilty could be the door set up menu. Some cars have a way of programming how the doors open when activated by the fob. For an example 1 push on the unlock button opens the driver door only, 2 pushes open all doors.