How to deal with frequent rotation of Passat electronic fan

Because the thermostat is broken, the electronic fan is always rotating, so it needs to be replaced immediately. The solution to the continuous operation of Passat electric fan is as follows: 1, the engine is overheated due to insufficient cooling water, and the electric fan continues to operate. Need to add antifreeze. 2. The engine is overheated due to water tank leakage, and the electric fan continues to operate because the hose is loose or damaged. The maintenance box needs to be replaced. 3. Even if the temperature reaches the reference temperature, the thermostat can't send water to the water tank, or the water supply is too small, the engine is overheated, and the electronic fan continues to run. The thermostat needs to be replaced.