Thanks Dallas, I just got off the phone with an Audi Tech and he gave me the same info you did. For a minute I thought I was the only one who believed that the compressor supplemented the defrost!

I didn't notice a sweet smell in the air, but there may be a film on the windshield -It's hard to tell with a faulty defrost and 86% humidity here. Is there anything else I can do to check it (short of using the gf's hairdryer to defrost the windshield and checking for a film?)

I hear changing heater cores is about as much fun as stabbing your pecker with a rusty screwdriver.

 

I understand that cooling the air using air-conditioner/compressor to dehumidify the air. What I cant understand is why the compressor needs to kick on to turn on the A/C to defrost the windshield. I work with buildings, and thats how they just work. I see chillers in the building the same for A/C's in a car. Excuse my ignorance. It's one of those things that it has to happen to me before I can understand it lol.

I can also recirc my air when its cold outside too. I turn it on when i smell fumes from other cars.

 

Mine would do that when a vent button would stick. Make sure all your buttons are gunk free and not pressing down