Hello everyone if your reading this thanks for the time. I have been Struggling with a friends 2004 1/2 sportsman 500. What it is doing has me confused. It will turn the fan on well reved up and as soon as it comes down to an idel it starts to flash a hot light. It didnt start to do this untill i put a a new fan in since the original went bad. Also at the same time i had to install the regulator/cdi update due to it wouldn’t turn on the new fan. Then i notice it wasn’t build any pressure in the cooling system so i tested cap and it was bad so i installed a new one. Still no pressure, so i took water pump cover off and found nothing wrong in there. I also removed the thermostat and boiled it seems to work fine. I also replace the thermistor in the cylinder head thinking it was bad. So all in all I’ve done alot of stuff with no result in the long run. I am open to others ideas and opinions. I have been in the repair business for quite a few years and fix lots of polaris atvs but this one has got me stumped> Thanks in advance for any advice.