I've had the same thing and Paul's response is right on the button. However, in my case although I managed to disassemble the multi plug that goes through the door pillar, all the wires were connected OK on the back of the plug. It was only a bit of good luck that made me check back further along the loom that goes into the door and lo and behold not only the big thick red-yellow wire but also a thin brown one was broken. They seem a bit hard to solder, so I crimped them and insulated them in the end.
Bit of a note as well. The multi-pin connector is an ABSOLUTE PAIN to get back in and the door pillar side seems prone to pushing back into the body. You need to make sure that you get the red/black rubber ring tightly into place holding the socket in place first, then get a helper to swing the door in slightly and hold it while you get the plug lined up. (it won't go back with the door fully open).
You feel the first click as the pins settle then you have to get a screwdriver to push the outer castellated ring clockwise which draws the 2 halves of the socket/plug together. Sounds simple when I write it here but took me a bad hour to figure how it all dissembles etc etc.
Make sure you know the person holding the door very well .... if they slip or let go of the door you're gong to missing some fingers :-)
John Simpson
May 2009