I just bought an '04 B6 and I looked through the owners manual, but can't find anything about the auto dimming compass rear view mirror in it. Can anyone tell me what the power button in the bottom center of the mirror does, it only lights a little green light to it's left and not the light on the right and when i turn it on and off and look in the mirror I don't see anything happening, but the compass does work correctly.

 

Anyone?