If the switches are working I would suggest a new start relay
Is the choke in the on position? Have you warmed it up enough?
you probly need a new heat sensor, its located on the bottom right of your rad, i had the same problem with my 700 the fan only worked when it was already over heating, i cut the wires flush at the sensor drilled a hole above the key switch and mounted a toggle switch, no more over heating,
its kind of annoying but theres a few choices on the throttle theres the tip of the wire get it with some needle nose pliers and pull it out of its seat and some times theres a c clip inside of it and remove it pull the through and then your good and for the choke it has a screw on cap sort of deal put your choke on half choke and and twist the cap thing and pull the choke through. also if the carb is bad and you want to replace it you can also twist off the top cap of the carb and take the needle off ( to do so you must pull the spring up to releive tension and then you push the needle through and once you do that the rest of it is childs play any more questions ask me ) i assumed this is a fan cooled if liquid there are different types of polaris carbs for the liquids i advice you bring it to the dealership because most new polarises have a trouble code thing and if you mess with it it could set it off and you wont beable to drive or it could cause further problems
My Sportsman runs bad when heated up, but if you add fuel it runs fine again. I had a pick up that had an internal fuel pump like our Sportsman's and it did the exact same thing. It turned out being the fuel pump was worn out due to a plugged fuel filter. Forcing the pump to fail prematurely. I found I had bad fuel in my Sportsman and am going to replace the filter and the fuel pump. I also checked my plugs, MAF sensor, and Air filter, they were fine.
I'm not sure but it might be the sensor on the right front wheel disk