I have a 2012 Ram 1500 5.7 l just had the motor rebuilt replaced got it installed starts up find everything works but now the electric radiator fan will not kick on try to change the fuse the relay check the relay shows that it's clicking has ohms and everything even replace with a new one still not working I even hooked up the fan directly to the battery and the fan will kick on change the thermostat temperature still not working

 

Do you have access to a high-end scan tool or AlfaOBD where you can use the tool to toggle the fan on and off to confirm the PCM is able to control the fan? Is the temperature gauge suggesting that the engine is reaching sufficient temperature that the fan should come on? Have you confirmed that the temperature gauge is reading correctly? Did the fan work properly before you changed the engine?

-Rod

 

I don't have access to a scan tool. The fan worked before the motor was replaced. I put a new temp sensor in and the temp went up to 255 by what the reading on the gauge inside. I put the old temp sensor back in and it read 210 degree and the fan didn't come on.