2 reflects the difference between the target cooling fan speed and the two coolant temperature sensor coolant temperature data of the relationship between the "Micro Cooling Fan" characteristics. When the engine outlet coolant temperature value detected coolant temperature sensor in the normal range, but the radiator outlet coolant temperature sensor detects that the coolant temperature is low, indicating that the heat sink temperature is not high, the role of "Micro Cooling Fan" Work is not, it should reduce the cooling fan speed; when the engine coolant temperature liquid outlet coolant temperature sensor detects a higher (already higher than the normal range), but if the radiator outlet coolant temperature sensor detects the coolant temperature also low, it means that the thermostat is faulty, this time to protect the engine and the need to control the "Micro Cooling Fan" high-speed operation.