FOREWORD
i know that a mod similar to this has been done on vfaq.com. the problem i had with it is that if you forget to turn off the switch, you'll drain your batteries as a result of leaving both fans on.

also, dino said that the ac fan turns on automatically if the underhood temps reach really high. in my experience, my ac fan on works when the ac compressor is running, but usually, it is off (i think if your about to overheat for it to turn on but i've never overheated ) so i don't know in my personal experience.

i have don't have any heating issues either other than the area above my turbo is hot (which is normal) but i want to have a fan directly blowing at the hot dp area and the exhaust side of the turbo for my 6 hr trip this saturday. sooo

PROCEDURE
shopping list: wire (used 10 gauge lying around), radio shack automotive switch with led light indicator, electrical tape, inline fuse, fuse,

the job itself is very simple. looking at the fuse box under the hood, look at the relays where the ac/cond fan-hi. that is the relay you will work with. the relay has 4 terminals total.
click this link to see the relay:

http://www.imagestation.com/mypictures/inbox/view.html?id=4213300323&url=http%3A%2F%2Fwww.imagestation.com%2Fpicture%2Fsraid79%2Fp4d9f6ba06eb43955e6a8388d7f59fcae%2Ffb21dc63.jpg&caption=phto0006_1

disconnect the battery
you will simply run a wire from the middle terminal (in the center of the relay), into an inline fuse holder. then the wire will run to the fire wall, and under the cosole to the center dash where you will mount the switch. you will then put that wire to the prongs on the bottom of the radioshack switch. then attach another wire to the lead under the radioshack switch and run this wire back to the fuse box under the hood where you started. looking at the photo above in the link, hook the wire coming from the lead prong of the switch and solder this line to the relay connection to the left/bottom relay connection.

on my radio shack switch there is another prong that is the ground. with the ground attached to a screw the led will light up.

with that your done.

put the battery back. put the switch back to the off. then turn the ignition switch and turn the car over. with the motor running, turn the switch on. if the ac fan should come on. turn the car off. then turn the key to the on position and turn the ac fan on. it should work. now turn the key to the acce position. the ac fan should turn off even though the switch in on the on position. then
take the key out, the ac fan is off even though the switch is off and your battery is not drained unlike the vfaq mod.

-------jezreel
hrc stage 1, sfmu, ml, prokits, egt, boost gauge, apexi tt, costum dp, dynotune fp gauge. gst muff, turbo spoiler