Mk6 rear door not locking

[Tippers123]

I have recently discovered an issue by pure luck that my rear passenger door does not lock with the remote fob. My brother in-law is a mechanic and removed the door card to take a look at the door lock. When the door card was removed there seemed to be a fair bit of moisture in there (probably related to this issue). He removed the lock and identified the unit as faulty. The lock responds to unlock commands from the remote fob, however when lock is pressed the lock just clicks but doesn't engage the lock. I sourced a new rear door lock from a VW trade counter and my brother in law fitted the unit, however the same issue occurs and the door still does not lock. He has inspected the electrical cabling in the door and all appears to be fine so I am happy the water ingress has not damaged it, plus the lock is shielded by the bottom of the window pane in the door. Has anyone experienced a similar issue or have any advice on potential issues that could cause this? My initial thoughts are the ECU has shut down the lock as it's detected it was faulty, if so how do I tell the ECU to detect the new lock?

Thanks in advance of any advice.

[Keithuk]

You need to get your motor scanned for any error codes logged in the ecu and post them, its no use guessing whats wrong.