Where is the thermostat located in the Passat?

[Hattie]

The thermostat of the Volkswagen Passat is located at the upper radiator hose. Function of the thermostat: The thermostat is installed in the vehicle to protect the engine operation and prevent cylinder explosion caused by excessive temperature during engine operation. If the vehicle does not have a thermostat, it will affect the vehicle's driving and, in severe cases, may lead to engine failure. How to check the thermostat's condition: You can judge by feeling the temperature of the upper and lower radiator hoses. First, start the engine and after 3 minutes, touch the upper and lower hoses. If the thermostat is functioning properly, the temperatures of the upper and lower hoses will be different—typically, the upper hose will be hot while the lower hose is cool. When the engine coolant temperature reaches around 90°C, both hoses should be hot, indicating the thermostat is good. If the temperatures of the upper and lower hoses remain the same after starting the engine, the thermostat is faulty.