My bro wants to do this custom fan switch. i want to make sure he wont go through the horror story that i went thru....the prev owners of my iroc rigged up a whole bunch of horrible bulls**t that melted down on me, making my car die completely in the middle of the street. i had to get the entire cooling circuit and starting circuit rewired.

but anyway plz give me any warnings so i can save my bro some trouble

 

No. The fan draws too much power to run through a switch.

If you don't have electric fans now your best bet is the stock relay setup from a jy. The stock relay is provided a 12v control when the ignition is on and grounding the relay passes power to the fan. The stock relay is grounded by the temp switch or the A/C pressure switch to engage the fan with high temp or A/C operation. Retrofitting this setup to an earlier model with mechanical fan is easy. To manually turn on the fans you can jump the control ground through a switch to ground.

I'd advise against using ONLY a switch for fan operation. Installing the temp sensor in the head is an inexpensive failsafe and a cockpit switch can still be used.

 

Yea . You can just hook up a switch to ground out the relay.. Better to do it that way. If you have a heavy enough switch you can just use a switch..But thats not the right way. Wheres your fuse in the pic??