If I put my AC in "auto" mode, and set a temperature -- doesn't matter what it is: I could set it to 75 degrees, while it's 50 degrees outside -- I can hear the AC compressor kicking in immediately. It wouldn't run for very long if it's cool outside, but what bothers me is that it would even run at all when the temperature difference is as such. The AC would run fine otherwise. When it's actually hot outside, the AC would cool down the cabin to a set temperature, no problem. When it's cold outside, the heater would eventually kick in and warm up the cabin as well. But it's that momentary running of the AC compressor that worries me. For now, I'm manually turning off the AC. What do you think is broken? thanks,

 

My car does the same. My guess is that it wants to remove humidity from the air that goes to the cabin.

When I'm staring the car, it immediately kicks in, but only for couple seconds. No idea how often it cycles while driving, as music if often much louder than compressor.

I just drive with auto all the time.

 

Sounds like things are operating as expected.

 

Pretty much all cars with automatic climate control run the compressor as needed. For my part, I press the Auto button, and then click off the A/C button and run in non-compressor mode (but otherwise still fully automated temperature control and vent selection) for most of the time.