In my 306, there is a break in one of the wires into the door on the drivers side - you have to either find and repair that - else replace the wiring loom. As a work around, I can press and hold the drivers button down, and then when it tries to unlock, keep it held down, then go round and manually lock the rest, but the probelm then is that sometimes it unlocks it self for you, so when you get back it's open.
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