How do you change a water thermostat on a 2.0 diesel x type jaguar?

To change the water thermostat on a 2.0 diesel Jaguar X-Type, start by ensuring the engine is cool and disconnect the negative battery terminal. Drain the coolant and remove the hoses connected to the thermostat housing. Unscrew the thermostat housing, replace the old thermostat with the new one, and reassemble by reversing the disassembly process, ensuring all connections are secure and there are no leaks. Finally, refill the coolant and check the system for proper operation.