Car air conditioning works by pulling heat out of the cabin air and dumping it outside the vehicle. It does this by cycling a refrigerant between a liquid and a gas through five main mechanical parts, while an electrical system of relays, sensors, and control modules decides exactly when the compressor is allowed to switch on. Most drivers only ever notice the mechanical half, the compressor, the vents, and the cold air.
An auto electrician diagnoses, repairs, installs, and maintains the electrical and electronic systems in your vehicle. That is the short answer. But if your car has just refused to start on a cold Toowoomba morning, your dashboard looks like a Christmas tree of warning lights, or your air conditioning has died in the middle of a Darling Downs summer, you probably want to know a lot more than that.