Yeh, it can be a pain in the neck, i have had to clean the contacts 3 times before. They are wearing down - I will need to get a replacement.
I needed the quick fix so I could put the window up before it rained. Turns out I found one!!!
You need to take the inside door panel panel off. Locate the electric motor. There will be a two wire lead coming from it. (blue and white if my memory is good). Connect them to a positive & negative source. I used jumper leads straight off the battery. It will either go up or down. Switch the leads and it will go the other way. Don't leave the connection on any longer than necessary, it may short something out. <img src="/forums/images/graemlins/lol.gif" alt="" />