What Controls The Fan in A Car?

The operation of the car fan mainly depends on the following technical means:
1. Methods for controlling the thermal switch
The thermal switch is a key component for adjusting the speed of the car fan. It usually has two independent gears and is placed in the water tank to facilitate the detection of water temperature. As the water temperature gradually increases, the thermal switch will send a signal to the control unit (such as J293), and then the control unit will adjust the rotation speed of the fan according to these signals. For example, when the water temperature is not particularly high but heat dissipation is required, the fan will run at a lower speed; when the water temperature is high, the fan will switch to a high-speed working mode.
2. Operation can be completed with the help of a temperature controller or thermostat
The electronic fan in the car may be regulated by a temperature controller or thermostat. When the water temperature reaches the peak, the temperature controller will activate the power supply and start the operation of the fan; when the water temperature drops to the lowest point, the temperature controller will automatically cut off the power supply, causing the fan to stop working. Using this technology can ensure that the engine operates normally in a suitable temperature environment.
3. Managing the engine and air conditioning system
Regarding the need for engine cooling: Electric fans are generally driven by electric motors. When the engine temperature rises, the fan will automatically start to take away the heat. This is a core link in the engine cooling system.
About the needs of the car air conditioning system: When the car air conditioning system is started, additional cooling measures may be required. At the same time, the fan may also start or accelerate its working speed to ensure that the condenser can dissipate heat normally. Although the air conditioning system and the electronic fan system are independent of each other, starting the air conditioning system does affect the working performance of the fan.
Fourth, the computer is responsible for performing control tasks, that is, ECU control
In some modern vehicle design areas, the control of the fan may become more intelligent. Whether it is the ECU (engine control unit) of the whole vehicle or a separate ECU, they may capture the water temperature signal through the water temperature sensor plug and operate the fan according to the preset temperature control scheme. The use of this technology can achieve continuous speed adjustment of the fan and more precise management of its temperature.
Fifth point, about the control system of the mechanical fan
For traditional mechanical fans, in order to reduce engine power loss and save fuel, the engine usually uses fan control devices (such as hydraulic clutches, automatic clutches and hydraulic couplings) to control the connection and separation of the cooling fan and the drive pulley. Although this technology may not be as accurate as electronic control, it is still adopted in some outdated models.
In short, there are many control strategies for car fans, including thermal switch control, thermostat control, engine and air conditioning system operation, computer drive control, and mechanical fan control devices. The comprehensive application of these control strategies ensures the stable operation of the engine and air conditioning system, while also improving the comfort of the car.