[mycbarnes]

Thanks, mine does not come on in the engine run position and confirmed with voltmeter no power at the fans. I did apply 12v with a battery to the fans directly and they work. I could not find a temperature sensor in the hydraulic reservoir, the pump or radiator fan motor, the Vickers solenoid body that controls the radiator fan, nor the heat exchanger itself. Which is why I was asking what others had experienced and it was bugging me not seeing the heat exchanger 12v fans working. Now thinking the DDEC computer controls the heat exchanger fans when the radiator fan is in the run position. But I haven't run it long enough to get radiator fan to kick in. There has to be a relay set for the heat exchanger fans, but not sure yet where. Probably in engine bay cabinet, but it isn't marked. No fuse found either, maybe a auto reset headlight circuit breaker can type instead. Once I figure out how it is wired I'll post a note. It's bound to help somebody who doesn't have working fans at all to troubleshoot.