The Ford website has information about how to properly add coolant fluid, but it does not offer troubleshooting information for coolant temperature sensors. People can find information about diagnosing and replacing coolant temperature sensors at CarsDirect.com and Howstuffinmycarworks.com.
Coolant temperature sensors enable the control unit to alert drivers if engines overheat or system temperatures rise. Different manufacturers install the sensors differently. Normally, the sensors are close to or inside the thermostat of the cooling system. Faulty coolant systems normally trigger a check engine light or service engine light on the dashboard of the car. Mechanics can usually identify any problems quickly.