Wiring Altima fans, a write-up

[matt4pl]

i wanted stock funcionality, where as most of the installs ive read about have the fans wired to turn on high with the car, which wastes power, shortens the life span of the fans, etc

this would make a nice sticky maybe?

now i have a diagram to post up of exactly what i did

here's the stock diagram, taken from the FSM i believe ( used the chiltons, its simpler, also, my diagram is based off the chiltons)



and this is the modified one



i tapped two 30A relays, one each into the stock relays, to control the power to the 2nd fan. i ran power from the terminal inside the fuse box in the engine bay to those relays, then out to the 2nd fan





then i ran the two new power wires out to the 2nd fan, made a notch in one of the covers for the stock harness, put the wires through there



I ran the ground wires to the battery but it's not neccessary, since you can ground them to the chassis anywhere or in my case, run them to one of the aftermarket ground wire connections on the motor

1st fan gets plugged into the stock plug



2nd fan gets wired to the two newly installed relays, the green wires are the power wires i believe



you have to pop out the stock relays, which is kidna a PITA, but its all fairly simple

Thanks to my buddy Paul (adikt on the forums) for figuring out the wiring for this, and helping with the wiring, as well as Konrad (shift knob, not on NICO i think) for pics and arguing about this

[ninjai]

from the look of the diagrams is your car an s14?

the only fan control on the s13 is the ac fan, which turns on at too high of a temp. None the less a temp controll sensor can be submitted for the ecu and all should be good.

I like it. Nice and basic as things should be.

[neilsan]

the stock s13 ac fan is plenty for my sr w/ koyo. I was actually really surprised how much air it moved... and the Koyo has mounting points for this fan for an oem-like fit. wired up a variable t-stat switch to a new relay that sees voltage from the brown O2 heater wire (ignition on)... works perty good. heatshrink tubing & aircraft grade splices are yr friend

[matt4pl]

yea, i do have an s14 and this write up is for s14's only basically. i like it, its basically the stock altima set up dropped into a 240

[SR240DET]

so this setup turns on only when it needs to be? doesnt run full time?

[matt4pl]

Originally Posted by SR240DET

so this setup turns on only when it needs to be? doesnt run full time?

exactly, good for the fans life span

[pr240sx]

most of the pain in the wiring is how to use the dual speed function fo the Alti fans.
I have mine basically like yours, but I have an S-13.
One circuit is connected to the AC, via a relay (30 amps)
The other one is connected to a adjustable thermistor (@ 180) via a 30 amps relay.
Why 30 amps, your are moving 2 fans
Wire gauge is also critical, you CANT use gauge lower than 12 (thinner) or you run the chance of melting something. Also use a god ground for both circuits.
My setup turn the fans on at 180F till 170F (via techtom) at single speed. If I am using the AC the fans also turns on (just like ECU) If both criteria met (AC and thermistor) the fans go into high speed.
Also, if the ECU "sees" more than 212F it will activate (via AC relay) then the thermistor will also "sense" the temp over 180 so they will switch to high speed.
Keep in mind that the ECU shut the fan off while using the AC at speeds over 25 mph, or if the AC temp control shuts down the compressor

[WILDACEX187]

pr240sx can u post some pix of your setup plz.

[SR240DET]

ok matt4pl.. i see you have low setting to turn on with the cars OG setup.. at what temp does the ecu send the signal to turn on the E fans?

[matt4pl]

the fans turn on low at 210 degrees, then go to high at a temperature not much higher then that, dont remember off hand