I have an A6 2003. A month ago I noticed that the battery voltage would be ok until I stopped and restarted. It would then only go up to 9-10 volts unless I reved the engine past about 1300 RPM! and then would be fine again...
The problem grew yesterday when the dome lights stopped working, so did the sunroof, and the display shows all door except the drivers door open!!! when I lock it, it also does not beep. All of this happened in the space of an hour!
Up until yesterday the dome lights would flicker when driving once in a while with doors closed and my wife also say them doing this with the keys removed from ign.

I can certainly use some help if anyone knows what the problems might be. I suspect the voltage reg. for the voltage issue but don't know how all of the other things happened all together, if it was a fuse why not the drivers door show open too? only the other three doors???

Please help.

 

Low voltage = strange readings. So, ignore the strange readings and fix the voltage issue (alternator or serpentine belt).

Bob

 

Take it to an Autozone or equivalent and have them run a free battery and alterator test. It could be a failing alternator but hopefully it is the voltage regulator, which should be cheaper to replace. Low voltage messes with the ECU and computer, causing all sorts of flakey errors.