My 2005 A6 is doing something very unusual. When its dark out and the lights are set to AUTO, the gauges, parts of the center console, and the doors do not illuminate. But if you turn the light switch to the ON position all the way right, everything works just fine.

I noticed that when selector is on AUTO, the interior lights will light up for a brief second, but will then turn off as soon as the HIDs come on (only in the dark). This leads me to believe that there is a problem with the light sensor that controls the automatic function of the headlights. I know on most cars light sensors are usually on the dash or mirrors, and I don't see anything in either areas that could be obstructive.

It's so weird, because I drove the car earlier today and it was fine...2 hours later it does this.

 

I'm having the same problem with my 2007 A6. Did u find out what the problem is?