Anyone have any diagrams how to go about hooking up a relay to the ECM to control fan on and off.

I currently have a thermo controlled fan that runs into a relay and is activated at a certain temperature, that I can set to what ever.

But I was thinking of just wiring it up to the ECM and setting the turn on TEMP on the chip and be done with it.

I know only one wire goes into the ECM to activate the fan but does anyone have a wiring diagram so I could have a look at it.

I have the pinout for fan on and fan off, just a little confused how to wire up the relay etc.

 

Go to your GM dealership and they will have the books. That or Chiltons.