汽车空调系统由制冷系统、取暖系统、通风系统和空气净化系统组成,其部件基本上都集中在发动机室内和仪表台上(图1)。安装在发动机室内的部件包括制冷系统的大部分部件(压缩机、冷凝器、储液干燥器、压力开关、冷凝器电子风扇和继电器等)及取暖系统的进液管和出液管等。而制冷系统的蒸发器,取暖系统的加热器芯,通风及配气系统的进、出风口,鼓风机电动机及调速模块,各风门及电动机,空调控制面板,车内温度传感器和光照传感器等都安装在仪表台上。因此,对空调系统的故障诊断可以分为2部分,即对仪表台 The car air conditioning system consists of a cooling system, a heating system, a ventilation system and an air purification system. The components of the car air conditioner are basically concentrated in the engine compartment and on the dashboard (Figure 1). Components installed in the engine compartment include most of the components of the refrigeration system (compressor, condenser, receiver drier, pressure switch, condenser fan and relay, etc.) and inlet and outlet pipes for heating systems. The cooling system evaporator, heating system heater core, ventilation and gas distribution system inlet and outlet, blower motor and speed control module, the throttle and motor, air conditioning control panel, the car temperature sensors and light sensors, etc. Installed on the dashboard. Therefore, the fault diagnosis of air conditioning system can be divided into two parts, namely on the dashboard