The visual inspection is a powerful tool to use when trying to spot problems in the AC system. Some of the mechanical items that are…

1. The control head should light up and respond to changing the settings. 2. The mode settings should change as the knobs are moved to…

The electrical systems that are needed to allow the AC system to operate smoothly are very important. Using a logical approach will go a long…

The duct box doors located inside the duct box can be moved by a cable, a vacuum actuator, or an electric actuator. Diagnosis of all…

Vehicles that do not use a belt-driven engine cooling fan will use an electric fan to control engine temperature and to cool the condenser when…

The blower motor is the device that forces the air through the duct box, and it is controlled by the HVAC control head. The speed…

The AC compressor clutch is driven by an engine drive belt on most internal combustion engines. The compressor pulley rotates at all times when the…

1. Perform the repair of the faulty AC parts that were found during the diagnosis process. All AC parts that were replaced during this step…

Vehicles that were built with AC systems that used R12 as the refrigerant were used from the beginning days of mobile AC units on cars…

The evaporator core is the heat exchanger located inside the duct box that causes the heat to be removed from the air that passes by…