If you buy a FIXD sensor it has a live data feature you can then use to scan the temperature sensor of the vehicle as well as many other things. It costs about $50 and is a great investment and its easy to use. You can check to see what temp the sensor thinks the car is and if it says it's normal temp then the relay to the fan may be stuck in the on position. There is a diagram in the owner's manual that should tell you which one it is. I'm not sure if the fan on my abarth is always on or not when the ac is running but I'll check and get back to you. but it would make sense for it to run all the time to help cool the ac condenser.