I asked this question 9 years ago and I still have not figured it out yet Here is the question: Aux fans come on when the air comes on they do not come on w/o the air. I thought that is how it was designed....wrong What I understand is that they should come on stage 1 when the coolant temp gets to 105C or 220F? If they still do not come on w/o air what can I check to get them working properly? I know there is relay and I know there is a ballast resistor where are these located and how do you test them and what else could it be? is there an error code for that?