So I have aftermarket fans (Mishimoto) and the other day my car over heated and when I got home I figured out my fans won't switch on. Then as I diagnosis them they turn on, then only one worked, now both are off again... if anyone can help I appreciate any feed back

Also I can't figure out what part of the wiring harness fans plug into just in case it's worse.

 

Have you checked the thermal switch located at the radiator? If it's not grounding at the set temperature the fans will never turn on.

 

Use jumper wires straight to the fans. If they turn right on they should be good, then the problem is either a short or the temperature switch, If not and you have to wiggle the wires or it doesn't spin very fast, it should almost jump out of your hand when you would have the fans off the car, then the fan motors are probably bad. Don't forget to check the relay it's not common for them to go bad but if it does they cost like $30 for some damn reason.