irenesbob

I am old and old school. I could live with a manually controlled HVAC system. I am always wanting it colder or warmer, so I wind up changing the settings anyway. Same thing with a lot of the features people can't live without these days. I have never used the seat settings because to me it is so easy to fiddle with the seat controls from time to time as my sore old back tells me to change the position. I guess it's a good thing I don't design Audi's (or anyone's) cars - they would be much more stripped in terms of features.
Still haven't opened the sunroof on my new A6 in the 7 months I've had it. One of the most important things to me (how the transmission downshifts) still sucks IMO, but most drivers these days are more concerned about how many contacts they can store for the phone and things like that.

IknowHuhA6

Wowza!
Based on a quick scan of the repair manual for HVAC, these are the sensors I found listed that affect the system.

Right foot well vent temp sensor G262
Humidity sensor G355
Sunlight photo sensor G107
Left Vent Temp sensor
Right vent temp sensor G151
Evaporator vent temp sensor G263

Left rear foot well vent temp sensor G637
Right rear upper body vent temp sensor G636
Left upper body vent temp sensor G635

Right rear foot well vent temp sensor G638

irenesbob

This number of sensors doesn't really surprise me, although I did not know the number. That is why I have been saying that having a big, sweaty driver like me on one side and no one in the passenger seat can lead to one side's vents blowing cold air while the other side is blowing warmish air; likewise for the effect of sunlight from one side..

AudiFan50629

I had the exact issue on my 2012 A6 last week, along with some other oddities. Air would blow cold only on one side, or the air wouldn't blow cold at all at random times.

The dealer replaced the AC Pressure Switch like you suggested under warranty, and when I went to pickup the car, things seemed better, but the air wasn't as cold as it should be. Brought it to the attention of the service manager, he agreed, and a complete drain and refill of the refrigerant then solved the issue after the pressure switch was replaced.

Hope this helps

rassi

Thanks! Any chance you would have a part number for the pressure switch at hand?

AudiFan50629

On my paperwork it looks to be 4H0959126A

Audi29

Thanks for the feedback!!!

David2017

62k miles, happened immediately after brake and oil change, strange. 80 degree out side, still blow hot air on passenger side. I have mechanics checked out the AC, no refrigerant leak found. read the thread, sound like pressure sensor issues, appointment with Dealer coming Monday.