Hi!
Some time ago I noticed that the rear view mirror stopped to dim at night. There is the photo diode in the middle of the lower part of the mirror, visually looks OK. Now the question - what is the most likely cause or causes for this failure and is it possible to repair it? Soldering is not a problem for me...

 

Check your fuses, I think it is fuse #14 if I recall.

 

Checked that, #14 is interior light (when door is open), #14 is OK. Do You have fuse chart somewhere? I suppose I have to order some good repair manual (which one is good?). The only one that I can get at this point at home is in Russian, terrible quality (translation etc...)

 

You can order a NEW manual directly from Audi here:
Audi Publications

 

Thanks for linkt.
Checked all fuses - all OK. Checked mirror connectors (there are three wires) with voltmeter - nothing.