I have a 2015 750 Special Edition and it is overheating due to the fan not turning on. The temperature light does not come on either. The radiator fan breaker is good, the radiator fan relay is working when I test it, the fan fuse is good. I applied 12 volts directly to the fan and it works. What input(s) does the ecu use to determine when it sends power to the yellow wire on the relay? I am hoping my ecu has not failed and want to rule everything else out. I should also mention that the resistance through the water temperature sensor is within spec at room temperature. Any input is greatly appreciated. I hope I am overlooking something minor.