Help with door lock please!

[Andy33]

2009 Audi A3 cabriolet sports 1.8 tfsi. I just bought this knowing it had an 'intermittent' passenger door unlocking problem. It was actually permanent and manifests itself as being unable to open the passenger door (ie left) from outside after unlocking with the fob. Once opened from inside, it can be opened from outside. I've found VAG door lock problems are common so I've looked at loads of stuff online. I first checked the door pillar wiring and it all seems intact so I bought a new lock (actually I bought two from different sources) and was willing to try swapping the lock. I removed the lock yesterday and found that neither replacement would fit! One fitted electrically but not the meachanical linkage, the other fitted mechanically but had a slightly different plug! I'm returning them. I also found it's not that easy to check the wiring continuity because the loom into the lock plug is heavily braided so you can't easily see the wire colours or even how many there are without cutting the braiding. Having got this far, it seems sensible to check the wires and the voltages so I'd like advice on how to do this. Should I carefully cut throught the braiding? How many wires are in the plug, what colours are they and what voltages are they meant to be please? If it makes a difference, mine has that auto-locking as you gain speed. I'm assuming there should be three wires: an earth and a signal wire for operating the locking motor and another for unlocking the motor? But why are there so many pins?

My second question is where can I get a replacement lock that will actually fit if the wiring all checks out and I still need to replace the lock? I have found it incredibly difficult to find the correct lock and there doesn't seem to be any markng on the lock itself to indicate the OEM number which would have helped. In the pictures, the dirty white one is mine!

[daveyboy1967]

I've replaced one lock actuator on my '03 A6 and have another one to replace. I got them on Amazon from a company called Frankberg for about £25 each, made in China but the quality seems fine and the one I've fitted is working perfectly. They're available on eBay too for similar money, I only used Amazon because the delivery was quicker and I was in a rush. Just enter your car details and you should get the right part, and the fact you now know what you're looking for in terms of connector type should make things easier. Hope this helps mate.