Hello the cooling fan in my 2002 Saturn SL1 1

Hello the cooling fan in my 2002 saturn sl1 1.3 liter only kicks on when the air cond. Is turned on. The fuse in box under dash is not blown of course, and I replaced the coolant temp. Sensor and it still does not kick on as it as should when car warms up. Also the 30 amp fuse at box under hood is not blown! Could it be the small square plug marked cooling fan on at top that
looks to to be a relay should I replace that? I am some what of a mechanic. Or can I check I t with ohm meterwhat do you think I just havent had any more $ to spend on it. I just put radiator and water pump in it not to long and should of taken care of this prob. Then but thought replacing the cts. Would do it but now since weather has cooled and not using ac. As much I see I still have prob. And I just cant afford to take to shop for diagnosis. I would be most gratefull for any in put on this matter thank you very much.