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Model X HVAC poor defrost /defog function-Normal or Malfunction?

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I live in NE Ohio where the heater/deicing is used a lot. On my Model X I have always had to manually turn on the defog function and have to continually play with it in fogging/icing conditions.

I got a Model S loaner that the defogging worked great. See the 2 screenshots. With the climate control on auto it would switch back and forth between 3 zone and defog only seamlessly.

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ModelS1.jpg


My Model X has never turned on all 3 zones or the defog only. It stays on the lower 2 zones. The only way I get defogging is by manually activating next to the seat heater icon. I pointed this out to the SC tech and tested my car and another Model X and said that the system is functioning as designed. Does everyones Model X require manually turning on the defog?

Ron

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I pulled my hair out trying to figure out defrost. For quite awhile, the only decent defrost I could get was by pushing the button next to the seat heater - and making darn sure it is red, not blue. The blue just will not defog or defrost my windows here in Portland on rainy days.

My Eureka moment was when I finally figured out that the A/C MUST be ON and the recirc MUST be OFF to get decent defog/defrost. Now I can set fan speed, mess with the vents and still get decent defog/defrost.
 
I am not sure I made myself clear on the original post. With my HVAC on Auto the defog zone, one of 3, NEVER turns on! I can turn it on by pressing defog on the bottom line of MCU or taking the HVAC off auto. Otherwise it will NEVER deice.

Tesla says this is normal for Model X but not normal for Model S, is that true? How does your Model X work?

It defogging conditions I have to constantly play with a system that is designed to be automatic.
 
V9 is a disaster. I sent an email to Tesla WRT this very problem. They are doing some funny things with the outside air, A/C, air direction, fan speed that they did not do in prior releases. This winter I have constantly been having to turn on the defroster whenever the temp is below about 40F and it's cold and humid outside.