To provide the comfortability in the vehicle room, we require a cabin spaces that can be adjusted to the desire of rider. The equipment of air conditioning system is used to regulate or control the temperature, including humidity, air circulation and cleanliness. Those papers aimed to understand the work principles, components, functions and work flows, refrigerant charge and discharge process, electrical system assembly, problem analysis or troubleshooting and performance improvement efforts as well. These final research method includes: concepts, tools and materials preparation, closed system assembly and refrigerant charge and discharge, electrical components assembly, testing and data retrieval, data processing of the testing process. As a method of observing these writing paper by collecting some data on materials object of the final project and doing literature review as a literature review related to the final task object of air conditioning system. Air conditioning system works based on the cooling cycle, refrigerant circulates through the functional component to produce a cooling effect by absorbing the heat, compressor rises its pressure, magnetic clutch connect and disconnect the compressor rotation, condenser perform condensation, receiver/dryer filtering and holding the refrigerant, expansion valve and evaporator to evaporate refrigerant and to absorb heat and electrical panel display as regulator or control and for learning in assembling of electrical circuits air conditioning system. There are problems and damages closed system refrigerant components, freezing evaporator, damage compressor and other components, clogged receiver/dryer and refrigerant charging when the air cooling effect does not match to the desire one. During the observation, examination and testing the results are obtained and function properly.