My '08 A3 S-line is about a year old now. When I first got it last winter, the climate control temp felt pretty accurate. I could keep on about 72 on a 55-65 degree day and it would blow warmish and keep the cabin around 72.

Lately if the climate control is on in the 70s at all even up to 84 (step just below HIGH) it's usually on mid/high blower and blowing cool air. Only if I click it up to HIGH (one step above the high temp read of 84) then it suddenly switches to very high blower and warm air.

It seems like any temp reading it's trying to get from the cabin thermostat is completely OFF and HIGH is just basically "turn the heat on" - no themostat control.

Anyone else experiencing this? Where is the thermostat for the interior? Maybe there's gum stuck in it (just kidding).

 

The temp gauge is located right between the dials were there are a few slats. I had the same problem happen in my Jetta that had climate control and to fix it I took a can of air when it was off and blew it clean. A few quick bursts until no dust comes out. After I then to an alcohol swab and ran it in as far as I could get and wiped around came out black. After that didn't have a problem up to the time I sold it.