How does the automotive electronic fan work?

The automotive electronic fan is controlled by a thermostat. When the water temperature rises to the upper limit value, the thermostat is turned on and the fan starts working. When the water temperature drops to the lower limit value, the thermostat is turned off and the fan stops working.

The high and low speeds of the electronic fan in the car are "solely" controlled by the thermal switch (F18). This switch has two gears and is installed on the water tank to detect the water temperature. It sends two gear signals to J293, and J293 then conducts different open circuits to control the high and low speeds of the electronic fan. When the air conditioner is turned on, both fans should turn. However, it should be noted that the air conditioner and the electronic fan are two relatively independent systems, controlled by two computers, named J301 (air conditioner) and J293 (electronic fan). J301 only gives a signal to J293 to force the two electronic fans to start. Apart from this, there is not much connection.

The electric fan motor has a large current when working, and has high requirements for the wires used. It will generate a certain amount of heat when working. The materials used in imitation parts are of low specifications and generate a large amount of heat, which can easily cause the vehicle to spontaneously combust. The electric fan rotates at high speed when working, and has high requirements for the manufacturing process. It is difficult for imitation parts to meet the design requirements for dynamic balance. When installed in the vehicle, there will be a large vibration, and after long-term operation, the vibration will cause the parts to loosen.