2016 Hyundai Tucson. A/C worked great, parked the car for a couple of hours, got back in and A/C did not work. Checked all fuses which were good, Checked freon level which was good, Insured compressor clutch was engaged, checked for leaks and found none. What should I be looking for?
Answer: If you are sure the freon charge is good and the A/C compressor is engaged, next make sure the radiator fan is running. This is what cools the high pressure side of the A/C system. If it is not on, then the pressures will be wrong and it will not produce cold air. Another thing to check is the lines. There should be an area where one line is hot, then it turns cold. This is the area of the orifice tube or similar. All vehicles have a way to divide the high and low pressure side of the system to produce the cold freon that cools the air in the cabin. The best way is to install a pressure gauge set and compare the low and high side. Low side freon pressure should be about 35 - 40 PSI and high side should be around 300 PSI. If these are not right, there is a problem in the system.
If all of these check good, and the A/C still blows warm in your Hyundai, then the system is making the freon cold but it is not cooling the air in the vehicle. So, now you would need to look into the temperature door in the dash that directs the incoming air either through the A/C condenser for cold or the heater core for hot. By switching the controls from hot to cold you should be able to hear the door change positions, or at least a change in air flow. If not, then there is a problem in what controls the temperature door. If an electronic system, then the problem could be in the controls or the electric motor that controls it.