The main function for cooling fan is to help radiator chilling down the cooling liquid，which belongs to automobile cooling system. The mounting position is located in front of the radiator , close to the car engine. The main speed control methods for fan are PWM and resistor. The fan motor with resistor control has internal thermal protection, good high temperature resistance and also can work at 100℃ for long-term , 110℃ for short-term. The fan motor with pwm control allows a soft-start to reduce inrush current and interference to other electronic components. The pwm module also has temperature monitoring of the electronic components and emergency run algorithms to protect electronics from damage. The Cooling fan module could save the space due to reverse shroud sealing.