Multiple Coolant System Symptoms

I had an over heating problem on my daughters car. It may be a combination of an air lock and a thermostat. Are you getting any water in the oil?. Take and put direct power to the fan by running a positive and negetive wire from the battery to the terminals on the fan.Keep your hands out of the way of the fan. This will verify the fan works. I would also replace the upper radiater hose as it may have lost its integrety. If it boils over the thermostat being stuck closed will seal and as water leaks at the overflow it would create a vacuem and collapse the hose. Do any codes show up on the computer. I have one saying cooling fan generic but I think it may be the sensor although the temperature gauge works and this is a secondary function of the sensor