Bought one a while back as I had classic symptoms, no door electrics etc etc. Looked at the wires between door and car and all seemed fine, so assumed it was dodgy unit. Had to pop a dent out of the drivers door the other day and found that 2 wires were snapped on inside the door not the rubber boot. Joined together and hey presto everything works again.
Anyway so I now have a:
A4 Central Convenience Module: 8E0 959 433 BD
p.s tried posting on for sale section and would go through. Sorry admins if in wrong area