The switch is installed at the bottom of the radiator and cannot be changed or repaired. You can check the function of the thermal switch by holding it over slowly heated water. You can also check the thermometer. Connect the test lamp in a circuit with the battery and two clips of the thermal switch and lower the end of the switch sensor into the water (see illustration). Make sure that the control lamp lights up at a temperature of about 88°C. Then let the water cool down and check if the control lamp goes out at 79°C.
7.1 Checking the function of the fan thermal switch