Get an AC inspection for your vehicle. This will determine if and why your AC is malfunctioning.
Understand the major components to auto air conditioning. --the compressor, compresses and circulates the refrigerant in the system --The refrigerant, (on modern cars, usually a substance called R-134a older cars have r-12 freon which requires a license to handle) carries the heat --The condenser, which changes the phase of the refrigerant and expels heat removed from the car --The expansion valve (or orifice tube in some vehicles), functions to similtaneously drop the pressure of the refrigerant liquid, meter its flow, and atomize it --The evaporator, which transfers heat to the refrigerant from the air blown across it, cooling your car --The receiver/dryer, which functions as a filter for the refrigerant/oil, removing moisture and other contaminants
Change the component that isn't functioning and make sure your AC is not leaking.
Check for bad switches, bad fuses, faulty wires, broken fan belts or seal failure inside the compressor. If any of those are the cause change them accordingly.
Safely and properly dispose of materials after fixing your AC.
Test your AC to make sure it is working properly after being fixed.Changing the air conditioner in a car can be difficult if you haven’t identified the source of the problem that has reduced its efficiency. Before you change your car's air conditioner be sure you know its exact location in your vehicle.