Mariociri

For all the greatness of my A8L, the heat function is very disappointing not to mention confusing. First, even when the car is warmed up and the engine is hot, the system really does not begin to blow very hot air for a very long time if at all. Secondly, why is it when I use the AUTO function, the AC light always turns on? Even when its below zero outside, and the heat is set to high, the AC light goes on. The Audi guy told me that's just how it works, but I have my doubts. I find the only way to really get any heat is to use the fan button only and never engage the AUTO button. My Benz driving buddy would not shut up while he shivered.

Anybody have any thoughts?

Ravill

Every vehicle I've ever owned turns on the A/C when I pressed "auto". My S8 is no exception.

If you look on the boards, there is a gentleman than just fixed his heating issues which sound somewhat similar to yours.

Good luck!

RED HORSE

The AC runs to reduce relative humidity which will reduce window fogging in cold weather.

Mariociri

Thanks, I just saw that thread. I have apt set for repairs. I emailed my service guy the threads.

Mariociri

Ah ha. I now have an explanation. Thanks. I did not think it was unplanned. Appreciate you answering.

subterFUSE

"Air Conditioning" does not mean cooling.

It simply means removing humidity. A/C can be running whether the climate system is warming or cooling the car.

Jack88

Mine ran all winter with the A/C off but the Auto setting on. I also have never had an issue with an inordinately long warm up time. Any difficulties with either merits a trip to the dealer.

Mariociri

With many AW forum assistance, I brought my A8 in for repairs. Actually met with the mechanic. He knew right away that I had a "N82 Heater Core Shut Off Solenoid Valve Stuck Closed". he replaced it. Of course, supposed to be 75deg today. Tomorrow, cold again. Will verify heat, but he told me valve was broken, so... fingers crossed.