A TOYOTA Camry car with a mileage of about 6.6 km. Owners reflect: the engine coolant temperature is too high, the coolant thermometer pointer to the red line, the engine powerless. In order to reproduce the high temperature of the coolant, the technician simulated the driver's driving, connected IT-II to DLC3, entered the menu / Engine and ECT/ data list, and monitored the temperature dynamics of the coolant at all times. When the initial temperature of the engine is 90 C (the engine has been preheated), the temperature of the coolant floats to 105, and the temperature of the ATF liquid reaches 103.3 degrees centigrade under the empty condition. The temperature of the continuous cooling liquid reaches 120, the coolant thermometer pointer is to the red line, and the multi-functional display screen shows "the abnormal temperature of the coolant". After receiving the car: analysis may be caused by radiator leakage or lack of water; radiator fans do not run; radiator blockage, radiator cover damage. Check the coolant enough, large circulation and small cycle normal, check the radiator without leakage with the SST test tool. The cover of the radiator is well sealed. When the engine is idle, when the coolant temperature reaches 97 degrees C, the fan operates at low speed, and the fan stops when the temperature drops to 91 C. Check the maintenance manual and circuit diagram. When the coolant temperature is 80~100, the air-conditioner condenser fan motor and the radiator fan motor are connected in series, and the motor runs at low speed. In the test, the coolant temperature reaches 120 C, the coolant thermometer pointer shows the red line, the multi-functional display displays "the coolant temperature abnormal", the warning light flickers, the buzzer is reminding, the engine feels weak, and the fan is running at high speed. What causes the temperature of the coolant to be too high? All of a sudden, the rescuer described the place as full of mountain roads. It rained continuously and the road was too bad. Could it be that the radiator blinds were blocked by earth? The lower radiator found that the radiator hole was almost blocked by earth. Troubleshooting: cleaning the radiator clogged windows. After washing, loading with cooling liquid to test the car, the coolant temperature is normal. When the coolant temperature is 95 C, the fan starts to run low speed, and the fan stops when the coolant temperature drops to 91.