I wouldn't necessarily jump to the aux. fan, mine hasn't worked since last summer and the A/C works just fine as long as I am not in stop and go traffic. I bought my new fan from Morristown, they have the best price I could find. There are two switches which activate the fan, a temperature switch on the radiator hose and a pressure switch on the A/C line, which starts the aux. fan when the A/C is running. I think you should go after the pressure switch before the fan.