Now that winter has arrived in earnest, my allroad has decided to fall apart. Although my questions can probably be answered by people with A6 or Avants as well.

1)The rear window defroster has suddenly quit working. Probably a relay? Do I have to remove the hatch interior to get at the wiring to test for power?
2)The windshield wipers have decided to come on for a random number of wipes when I turn on the ignition. Relay? Or, gulp, switch?
3)Rear window washer quit. Makes noise like it's pumping, but nothing comes out. Is it the same tank as the front washers? Different pump?

This on top of a leaking fuel rail repair.

Any assistance appreciated.

 

Not sure how much of my knowledge applies as I have an '05 A4 avant but first thing to check with a defroster that doesn't work is the little connector from the wiring to the actual window. They are most often the culprit. They come loose or disconnect completely or often corrode. Not sure what to make of the wipers, that's a new one to me. If the allroad has the same style washer system as the A4 then there will be one tank but multiple pumps, probably 2. I didn't find the pumps to be all that expensive but had a hell of a time getting at them.

 

Check to see if the nozzle on the rear washer is plugged. I just bought a 03 Allroad and I could hear the pump working but no fluid. Remove the plastic cap that covers the bolt to hold the rear wiper on and pull out the nozzle. You may need needle nose pliers as they can be very tight. Once out take a small pin or wire and run it through the brass part of the nozzle to free any sludge. I also ran in the opposite end and removed a lot of stuff.
Once re-installed you may have to aim it at the correct spot on the window as I had mine shooting fluid onto the roof. Hope this may help.