Im running a dc mishimoto rad with 2 12" fans , now i have one hooked up just like the oem fan would normally go on. But i would like to wire the other fan with a switch inside the car so i can turn it on for track days or if the other fan fails.

Now is there a way i can wire the fan into the lets say the defroster button? i dont wanna add switches to the interior. i even though about running a fog light switch to trigger the fan but i cant get it to work. Im running the wires through a relay and fuse just to be sure dont want a short

 

I have this same setup - it's super easy if you would just put it on a switch. Why don't you want to add a switch? You can find OEM looking ones for cheap.

 

i guess thats what i'll have to do , can u tell me how u wired it up?

 

For sure man, it's really simple - fans only have two wires; a ground and a 12v

For the one that is to be controlled by the thermostat, splice the OEM wires to the new fan. I made it so I can just use the OEM plug.

For the second fan - Run the fan's ground wire and ground it to part of the chassis. Then wire the fans power to one side of the switch, and from the other side of the switch, run a wire to your battery's pos. cable post. Usually you can tap into the fuse box for this. 10 gauge wire should be fine, and get a switch rated for at least 30 amps

 

I was trying to run everything through a relay and a fuse just to be on the safe side. maybe im wiring somthing wrong on the relay