BESTDAY

2005 A6 - Anyone have issues with their Heater coming on by itself? Extremely hot air begins to blow in side vents at unexpected and mostly inopportune times, usually in summer or warm days. I always keep system on Auto. Sometimes it begins to blow shorlty after starting car, other times it is in the middle of a drive, the fans kick in to high gear and the heat pours out. Very little success in getting it to stop during that drive. I usually have to stop and let the car cool off overnight, but I have had success in adjusting the configuration/direction settings but it is dangerous while driving ...

AV8TORSADF

Sounds like a perfect time to visit the dealer, especially if you have warranty left.

BESTDAY

Thanks for your post. The Warranty is expired. I had this same issue while it was under warranty and they "fixed" it, but a couple of years later, and it has re-emereged. Regrettably, I did not extend the dealer warranty.

AV8TORSADF

Was it fixed a long time ago? If not too long you might be able to persuade the dealer that it's the same issue and they never fixed it or at least give you a break on the cost of repairs.

mstams

My wife's former 2006 A6 4.2 had the same issue right after the warranty expired. We just traded it, so problem solved...

4567

I had the same problem. Every once in awhile, maybe 40 minutes into a trip, the AC would cut out and blow blazing hot air instead.

Dealer replaced a faulty water valve in the climate control system. Haven't had the problem again so far, but its only been a couple of months.

Good luck getting it sorted out.

whall

Any idea of the cost to fix?

I just hit 50,040 miles and this started to happen.

haha bye

weird keep us updated on this...I think its a water valve...

05whtaudia6

Wasn't the repair explained on the service print out?

mastermindmd

There is a TSB out for this exact problem. Mine is doing the same thing and is out of warranty. Took the TSB in to the dealer and they will contact me if it is something they can cover anyways (out of warranty for only four months). If not, the extended warranty will pay for it.