Cadillac SRX Second Generation Forum - 2010+ Discussion, Climate control on "auto"- A/C comes on? in Cadillac SRX Forums; When I turn the climate control to "auto", the A/C light comes on? Is this supposed to
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The AC coming on is common. I suspect its part of the "auto" system so it can both heat and cool the car properly and maintain the selected temperature. It also prevents the windows from steaming up on the inside. You can always turn the AC off which is what I sometimes do.
The AC compressor is not on because the light is indicated on the dash. The compressor is available.
This is how most "auto" climate controls work. Reason being is, the car is monitoring the interior air quality. Even in the middle of winter, if picking up 4 kids after basketball practice, the car needs to get rid of that humidity. In order to do that, it needs the compressor. Thus, "A/C" is active, even though its 20 degrees outside.
The car will also monitor the system and not run any system that could be damaged due to outside temperature.
Its designed that way, and I advice people to leave the Auto on to allow the car to properly condition the interior compartment and dehumidify it as required.