Thanks for the great information. This weekend I'll start by taking the door apart and thoroughly checking all the connections in there to make sure there's nothing suspicious then move onto the control unit. Sounds like the control unit may be a job for my Indy if it requires coding.

__________________
2003 X5 3.0d | 20" Style 168 Wheels | Dice Mediabridge | AE Headlight Upgrade | Invisibulbs All Round | Pioneer 10" Sub in custom enclosure | ECU Remap