How do you change the thermostat in a 2007 Ford Fusion?

To change the thermostat in a 2007 Ford Fusion, first ensure the engine is cool, then disconnect the negative battery cable. Drain the coolant from the radiator, and locate the thermostat housing, which is typically found near the engine block. Remove the housing by unscrewing the bolts, take out the old thermostat, and install the new one, ensuring it’s oriented correctly. Finally, reassemble everything, refill the coolant, and reconnect the battery.