As per title - when using the keyfob to lock the car the rear passenger side door doesn't lock, all the others do including the boot. It unlocks everytime, and locks if I push the tab down.

Any ideas? I'm guessing a vacuum leak but why would it unlock and not lock?

New lock mechanism required. About £100 from the stealers or about £40 second hand. You will need correct torx and spline drive sockets if you are to do it yourself. It's a little fiddly but not hard.

Probably as said ^

Though its maybe worth checking the wiring first to make sure nothing has come loose

Thanks for the swift replies guys - I'll have a look this weekend. Any idea of part no.s or if any other cars in the VAG family share the same part?

Mate, I had a similar problem. I removed the door card, carefully cut the plastic sheet, used the remote to unlock and lock to see how the mechanism worked. It was clear that electric was getting to it but it was catching and a bit stiff. I lubed it all up (fnarr fnarr) and it now works fine. I stuck the plastic back up with

parcel tape and replaced the door card and it's worked fine ever since (over 2 months ago) apart from 2 random occasions. Might save you some cash so hope it helps. Give me a shout on 07908 035200 if you need any help

As above, I did the same to my rear nearside lock but also sprayed lubricant on the parts of the lock you can see with the door open. Used VAG ptfe filled oil spray and it has been ok since the Spring.

Thanks Bagel and Pikpilot - I'll give that a try!