I have an 06 Ranger 500 carb'd. I have been having an issue. I can ride for 20 minutes or so and the ranger shuts down as if it is overheating, but I never get an overheat light. I know the light works because it came on when I disconnected the fan during troubleshooting. I have read numerous posts and no one has the exact same issue. The coolant system is working as advertised with good flow and no blockage in the radiator. One thing that I find abnormal is the fact that when the fan turns on, it is only on for 30 seconds or so and turns off. Typically on every Polaris I have had, they stay on much longer, especially sitting at idle. Shortly after, it sounds as if the motor goes into a safe mode, or fuel is shut off, and then dies. It will even die if I run the fan straight off the battery. If you let it cool down for 20 minutes or so, it will fire back up and run until the cycle starts over again.


I've done everything I can without throwing parts at it (radiator clean/flush, connector cleanings, run fan to battery, check voltage with/without fan on, etc.), but I suspect the ECM is to blame. I'm not usually about buying the most expensive parts first, but this seems like the most likely culprit. Any help would be greatly appreciated.

 

Think you have the problem pegged. I've had several Rangers do the same thing. Once the ecm got hot,lost power to the ignition and dash lights and would die. Several on ebay,but cheapest I've found is at Partzilla. 4011089 MODULE-500 ECM $251.99 http://www.ebay.com/itm/polaris-ranger-500-4011089-ECM-ECU-Electronic-Control-Module-charge-regulator-/261947104047?hash=item3cfd439b2f&vxp=mtr

 

Thanks! That's another thing that had me wandering if, in fact, it could be the ECM. Nothing else shuts down but the motor, but I've heard the ECMs in these 04-06 carburetor Rangers can give you all sorts of trouble.

 

Yes,the ones I had shut down power until they cooled off. One way to possibly tell is check voltage on the wiring harness coming in and out of the ecm when it's cool,then checking again when it dies.Plus some have pulled them apart to find burnt areas or melted circuits.Mainly it's the solid state circuit breakers that trip when hot,then when cooled down they will work ok until they get hot again.