I have a 2015 BMW X1. I notice when I use the “auto” climate control function, it has a tendency to also illuminate the A/C button (turn it on). I’m curious as to why the A/C would want to turn on too, if my temp setting is for 71 degrees and it is 40 degrees outside. Thanks.
The AC runs to de-humidify the air inside the car so fog does not form on the inside of the glass and obscure your vision.
Mustangman is correct. Remember that it’s “air conditioning”, not “air cooling”. Removing humidity is part of conditioning the air.
In addition, the system needs to be run from time to time to keep everything in working order. This is sometimes mentioned in the owner’s manuals of cars without automatic climate control.
That makes sense.
Driving with windows closed would cause a buildup of moisture from normal human breathing.
Sometimes I will turn the AC on and direct it to the window to defog it.
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