Originally Posted by TheOtherDave™
There is a coolant temperature switch that controls the radiator fan operation when the AC is turned off. Since the fan came on when you activated the AC, it is very likely that the coolant temp switch is dead.
Does this mean that if my fans don't ever come on, it is unlikely that buying a new switch will solve my problem? Also, how do I test to see if the fans themselves still work? Thanks.