DIY: How to wire up an Electric Fan
 

I saw that Mishimoto posted this over on Tristatetuners.com, so I figured I would post it over here for you guys. I searched a bunch trying to see if this was covered already, but I found nothing.

Materials Needed:

- 1 x 5 post relay
- 2 x 10 AMP fuses
- 15 feet of 18 gauge wire

Instructions:

Run a 12 volt positive wire to the relay (put a 10amp fuse in this wire). The other side of this relay is the positive connection to the fan.

The ground from your fan can be grounded to the body of the car. Make sure it’s a good ground.

Find an accessory wire to tap off of. This is a wire that becomes hot when the key is in the “on” position.

Tap a wire off of the found accessory and run it to the switching side of the relay (put a 10amp fuse in this wire), and then ground the other side
of the switch.

Wiring your fans like this will make them turn on when the key is in the “on” position (when the engine is running).

Please refer to the wiring diagram below.

Attachment 8937

Hope this helps!

problem is that the fan will always be on.

haha. Good observation. I rigged mine up with the key.

I ran my fan all the time and with a proper relay had no voltage drop... the stock fan works great but just takes up space... It runs all the time but........ as we all know its mechanical.

jbt_92 do a write up on how you did it for the ignition is what it sounds like your saying.No offense to BR, but personally it will drive me crazy to hear that fan running while the car is off.

I personally like how the fan turns off when the car turns off, just my .02 cents. Batteries are costly and im in need to waste my battery like that.

BTW its still a nice right up.

^^^^
did this guy get banned for being a complete idiot?

By the way theres a couple problems with your post, and its obviously mishimoto's fault if they are the ones who made that diagram...

first off: you need to know what amperage the fan uses to decide what size relay to use.... if the fan draws 15amps, then you can use a 20/30amp relay, if it draws 25amps, then use a 30/40amp relay

secondly: you dont HAVE to use a 5 pin relay, you can use a 4 pin just as easily, considering you will be leaving the 5th pin on the relay unplugged anyway (pin 87a) so there really isnt need for it.....

third: theres no reason at all that you need to put a fuse on the 12v switched portion of this circuit... there should only be a fuse between the battery and the relay measuring the same amperage as the relay (ie: 30a fuse for 30a relay) , and a fuse between the relay and the fan the same size as whatever amperage the fan is pulling.

fourth: youre also going to have to ground one of the pins on the relay...

other than that its a good write up, youre just working off a really bad diagram through no fault of your own.

......... keep your clutch fan

:)