I have a 2002 Rancher 350 ES and the cooling fan motor is not working. Is there some kind of coolant sensor on this bike that I just haven't seen yet. I haven't pulled the fan out yet, wanted to get new one before doing so. But if there is a sensor that could be the problem, it has to be cheaper than the fan itself.

 

This is the oil cooler fan that has a temp sensor to control it.

You can disconnect the motor and apply 12 volts to see if the fan will spin and this will tell you if it's the sensor or not.

Have you had this atv since it was new or is it new to you? Reason I ask is that I used to own an 05 Rancher with a manual tranny and the cooling fan only came on after extensive slow driving in hot temps.
Driving fairly fast, it hardly ever came on.

 

If its turns out to be the fan,these guys are much better priced then OEM. SPAL USA