Champion fan relay, odd shutoff issue.

What Dana said. High side Power would come from the battery to the thick red lead on the relay, and jump across to other thick red/orange wire that goes to the fans. The thin wires one should come from low draw power and the other from the grounding of the Thermo switch. In line of the thermo switch, you can put in a splice to switch to ground to activate the fans by the switch. It will also activate when the thermo hits temps, grounds and turns on the fans...