Is a air conditioner pump and air compressor pump the same on a car?
The ASE tech isn’t mentioning another belt driven pump. The A.I.R. pump injects ambient air into the exhaust to accentuate catalytic converter processes. It does not have a clutch and runs all the time. Air flow is managed by diverter valves into the exhaust stream or into the cylinder head. The AC clutch cycling is either normal or a little low on refrigerant. In low temperatures the properties of the refrigerant change. This causes the low side pressures to run lower and the compressor is cycling to prevent evaporator freeze up and maintain oil flow through the system. Even if your air conditioning is turned off the compressor may still function. For instance in Defrost mode the air conditionng is used to dry the air for the windscreen. Air conditioning is 80 percent dehumidifier and 20 percent heat transfer.
