The windows in my 955 Cayenne Turbo kept fogging up in very cold weather and were slow to unfog.

After a diagnostic scan with an iCarsoft, I found code 1596 (servo motor for fresh air/air circulation flap) — the fresh air flap wasn’t moving. I confirmed this by looking at the live values of the servo.

I followed the procedure for air cabin filter replacement — the servo motor is right of the air filter, connected to the flap with a white plastic arm. I unhooked the arm, wiggled the flap loose (it got stuck somehow)

I verified that the servo worked (visually with the arm disconnected, then with scanning tool looking at live values)

15 minute fix, $0 spent.



No more fogging issues afterwards!

 

I have iCarsoft and don't remember ever getting to that screen. I think I would get a communication error when I tried to read anything for HVAC.
I don't want to go too topic but I'm wondering if my iCarsoft is set up right.
Do you find the automatic mode to be useless and a waste of time? I have to always go through each system one by one.

 

You can update the iCarsoft (download the new firmware from the website, copy it to the SD card) — it seems to fix a lot of bugs.

I use the manual scan; the automatic scan doesn’t really seem very useful.

 

Hmmm, it has been a few years since I last checked for an update. Worth a shot, thanks.
btw, I recently had a fog to my windshield after starting off (cold weather also) and it turned out it was my sunroof drains* leaking near the footwell.
I had done my cowl drains but never did locate the sunroof drain plug things. Just a thought in case your fog ever returns inexplicably.
Sounds like you nailed it with the fresh air door thing, though.
Thanks.

*truth be told, I still haven't verified the source... I'm using the process of elimination. I also haven't checked my AC drain, but I'm under the impression that that only deals with water when the AC is on.

 

If you're using the HVAC system in Auto mode, your AC Compressor is on. Only shuts off and doesn't run in ECON mode.

 

Not when it's cold out. I live in NJ.

 

yup itll turn off if its too cold.