Pontiac Repair: 98 sunfire 2.2 engine fan switch?, engine fan, fan switch

Question
Good Day
I have a 1998 sunfire 2.2, auto with air. Engine fan does not turn on until temp. gauge gets near yellow. I have been told a common problem use to be corrosion on the coolant switch that controls the ground side of the fan control relay. However, I am unable to locate it. Do you know if there is one or does the pcm control the engine fan?

Answer
ok well first off , try a new thermostadt and see if that will help, its a cheap thing to try first, the fan switch usually are good/ bad  normally, i would do this drain the coolant flush the radiator and then put a new thesmostd in and see if that helps first, as long as the fan is cycling it tells me the fan controll circut is ok, does the fan seem to be moving at a high speed to move the air and cool it down when it com,es on?