Here we have a Ford Focus that came in with an overheating problem.
First thing we found was that the coolant level was very low.We then pressurised the coolant system only to find the thermostat housing was leaking.So we replaced the housing with fresh coolant but still overheating?.Was there another problem or problems to try and find ?.There was, the cylinder head temperature sensor (that screws in to the cylinder head had gone faulty).This made the engine cooling fan stay on all the time, because it was reading over 100 degrees c !. We replaced the sensor as well but still no radiator fan working at operating temperature.We then had a quick check of the radiator fan wiring and block connectors and we can now see why our fan is not working (pic). Because of the fan stuck on all the time it heated up the rad fan block connector and pins (they burnt out).We carried out a repair on the pins and block
connector (bingo) fan back working.So you can see how one problem has a knock on effect with others.