Headlight problem, still got

[TWFAUST at aol.com]

I have posted this one to the list before, but here is the history. The car 
is an '82 Coupe with the four headlight system. When I got the car a few weeks 
ago, the driver's side low beam was out. Because of this it failed inspection. 
The inspector pulled the socket and couldn't find power. He also couldn't 
find it at the fuse. Leaving the inspection station, I stopped by an upholstery 
shop. For whatever reason, the upholstery guy had a look. He disconnected the 
light socket and reconnected it. The low beam came on. 

A few days ago the light went out again. It had been a very cold week and 
list members have suggested the switch is temperature sensitive. Using a test 
light, I am unable to find power at the socket or the fuse. List members 
suggested it was the switch. That seemed logical since Audis run the power through the 
switch. I couldn't get a new on so I took one from a 70K '86 4000S I came 
across. I put that switch and the problem persists. It is possible the switch is 
bad. 

I await arrival of my eBay Bentley.

If anyone has a diagram available, I would appreciate the following:

Color code for low beam wire from the switch.

Am I correct in assuming that there is only one low beam wire from the switch 
and that it divides somewhere before the fuse box. I have heard of Audi 
switches burning, so I am assuming that the fuse is after the switch. Is that 
correct?

Thanks to all who have assisted so far.

Tom Faust