If you're happy that the mechanical cables were all connected properly and not broken when you replaced the lock mechanism (it would have been obvious and unusual to break) the other electrical area that can commonly cause problems (Audis and other cars generally) is the wiring going through the door at the inside edge. Basically, the continual opening and closing of doors, over a period of time, can cause a copper wire (s) to fracture. You need to pull back the protective rubber sleeve and examine. If broken it's best to solder and cover with shrink wrap.