Raidiator fan wiring

[SubaruNation]

I am trying to wire my fans so they come on whenever i turn the car on. does anyone know which wire is which?

am i safe in assuming black is ground and one of the other two is signal? i can take a picture too but there are 3 wires... 1 signal and 1 power and one ground... im basically not sure where they lead into the fan itself.

2 wires lead into one part of the fan and 1 goes to another part.

any ideas?

thanks

[kimokalihi]

I'm guessing the two wires going into one part of the fan are power and ground while the third wire going elsewhere would be the turn on lead. Easiest way to find out would probably be to break out your multimeter and test for voltage when the fans are off with the car on. Whatever wire has 12 volts is probably not the signal wire.

[93forestpearl]

Don't wire two fans on one of the fan relays. Mine lasted a year like that, and failed at a very inopportune moment.

[SubaruNation]

SO.. since im L33t as hell, i made a MSpaint diagram of what it looks like.



basically this is a depiction of what the whole system looks like from behind.


i noticed that when i grounded out the single fan... then connected both the green and blue power wires to direct power from the battery, the fans went Super Saiyan. (meaning they were reeeal powerful.. think Majin Vegeta)

when i connected power to just one of the green/blue combination the fans didnt spin as fast.

do you guys have any ideas on how i should wire these up? i was considering just a fuse in between stuff just in case there was a surge.. so the fans dont blow.

thanks for the help!

[SubaruNation]

also my fans would not turn on at all... most likely due to AEM drama which i am just going to bypass by wiring them in from teh battery/ the same line as my foglights.

also also when i checked for power current running through the wires with my light meter... i got nothing. maybe because the engine wasnt "hot" or because of aem drama.

thx!

[93forestpearl]

The ECU should have two fan control connections. I don't have the diagram open at the moment, so I'm not sure.

There are no control wires at the fans themselves. The relays are in the fuse box in the car. So, work your magic between the ECU and the interior fuse box. Make sure you have solid wiring to the fans. If you run all the power for both fans through one factory fan plug, you will melt the plug. I did. Use two separate plugs for the fans, and both factory relays, or aftermarket relays rated for over 30 amps.

[kimokalihi]

i noticed that when i grounded out the single fan... then connected both the green and blue power wires to direct power from the battery, the fans went Super Saiyan. (meaning they were reeeal powerful.. think Majin Vegeta)

Please tell me that's not a dragonballZ thing.

[impreza_GC8]

There are three wires on each fan plug. Ground, low speed power, high speed power. I'm in the process of removing my two fans and replacing them with a single, larger fan. I'm having a hard time sorting out the wiring myself, but I was able to work that much out. I think I'm going to bridge both of the power wires from a single plug together so that my fan wont turn off when the ECU tries to switch speeds. We'll see how it goes.

[Legacy777]

Let me see if I can help.

I would say for about 99% of you out there, the fans should be wired on "high speed" from the factory. Unless someone has done something with the sub-fan short connector, the fans should be wired for "high speed" operation.

Here is the factory wiring diagram for just the radiator fan setup.

http://main.experiencetherave.com/subar ... iagram.pdf

As you can see the sub-fan short connector ties into the same power supply lead.

If you look at the AC wiring diagram it is MUCH more confusing

http://main.experiencetherave.com/subar ... ngdiag.jpg

The jist of that drawing is this. The main fan is on "high speed", and the sub-fan is on "slow speed" unless the sub-fan water temp relay activates to "high speed".


Now....for your custom setup, I would really just keep the stock wiring how it's setup (with the sub-fan short connector connected), and use the existing pin at the ECU to activate the radiator fans through the existing wiring/relay setup.

If that's still not clear, let me know.

edit: Just one thing to add.....the ECU does not control in any way fan speed. The ECU just controls on or off.

[skid542]

This is an interesting thread because I'm going to wire up my two wire fans this weekend and have been wondering the same thing since I have three wires from the stock harness. Infact I've asked about it and I've stared at the FSM's but I'm not 100% clear (I'm a bit electrically challenged sometimes). What I get confused about is which connector is the sub fan connector?

My plan was to take a fan, wire it up to a stock plug, from the fan side, and hook it up to the stock harness. Then turn on the car (motor not running), plug the temp sensor connector to an extra temp sensor I have laying around and then put the extra sensor into a cup of boiling water. At that point the fan should turn on, or it won't. If it doesn't then I swap the pin position of the non-ground pin and try again and ensure the fan comes on. At that point I repeat for the otherside (passenger side).

As I understand the system, each connector (driver and passenger side) has three pins. One pin is obviously ground. One pin controls the high speed setting which is driven off the temp sensor. The other pin is the low speed setting which is driven by the AC system. Correct?

If this is a reasonable approach then I'll have an answer on which pin does what late tomorrow night and can share my results.

[Legacy777]

Lee,

Your assessment is not quite correct.

The sub-fan short connector is located around the passenger side headlight area. it's a jumper type connector.

On the main engine fan, with the sub-fan short connector connected, there is absolutely no low & high speed fan operation. It's just one speed, high. So if you're looking to use a 2-wire fan, it should not matter which power lead you hook up to.

On the second fan.....assuming I'm reading the diagram correctly and subaru did not change anything, I would find the lead from the sub-fan relay and tie that into my 2-wire fan. You should be able to just pull the sub-fan relay from the fuse/relay box and check for continuity at the sub-fan connector. You could also use your method as well. Really...you could just connect the green diagnostic connectors and the sub-fan relay should cycle on and off. That'd be easier than messing with the coolant temp sensor.

[SubaruNation]

i noticed that when i grounded out the single fan... then connected both the green and blue power wires to direct power from the battery, the fans went Super Saiyan. (meaning they were reeeal powerful.. think Majin Vegeta)

Please tell me that's not a dragonballZ thing.

Kimo: Final Flash, yep.. game over.

So!...

I made this diagram because the other one is nothing near the existing wiring setup on my car, I wish it was though josh




is this something that i can do?

I understand wiring but only mine i guess... if that makes sense? im not that great at reading pinouts.

Can you maybe lend me a hand Josh?



Also: i mentioned it, bet there are 2 speeds on each of these fans... or maybe the super saiyan mode im seeing is because im overloading the fans with power? if i only use one of the 2 wires (per fan) for power.. then they will move half as fast but i wonder if that will be fast enough. ill probably burn them out pretty fast if i have them wired in all the time for double speed. ugh!

[SubaruNation]

bump for help from josh

[skid542]

FWIW, I got my fans wired up today. There are three pins on the chassis harness side connector. One of the outside pin is ground - this should be easy enough to sort out. I then ended up using the center pin on both the drivers and passenger side for the positive for each of my two wire fans.

I verified that the connections worked by taking a lighter to an extra temp sensor and watching my scan tool. As soon as I hit 205*F both fans kicked on like they should. Typically when I see my fans on is when I'm either racing or sitting at a stop light so I took my test to be an accurate representation, i.e. speed sensor at 0 and temperatures over 205*F.

*On a side note, it was neat to see how quickly the temp gauge actually reacts with the lighter. It was surprisingly sensitive.

[Legacy777]

Zach,

Are you wanting to run these fans all the time? I don't see why you couldn't hook them up to your AEM to turn on when coolant temp reaches a certain point.

You need to run the fans off of a relay. Each fan needs their own relay. I will try and draw up a diagram later today and post.

[SubaruNation]

Josh,

Essentially my tuner recommended that i "bypass" the AEM and run the fans just all the time, since i do have a ginormous turbo and it does get really hot anyway. ..especially since i only have the stock radiator.

I'm sure i could find the pinouts and see exactly where the wires go, and set it up within the AEM, and i plan on doing that. i have to look through old tuning maps and find the right one where the fans worked, and hope i can get it running that way, in the meantime having them running all the time cant have hurt too much.

If you could make a super simple diagram similar to my MS paint skills above that would be awesome.

thanks josh,

[Legacy777]

I'll work on the diagram now.

I don't agree with your tuner. You really should have some form of fan control. All you need is one input and output on the AEM. I'll make the diagram so the fans are on all the time with the ignition. But I really suggest you get it setup so the AEM controls them.

[SubaruNation]

that would be sweet, i went to napa and this guy told me about this sweet coolant sensor deal from a saab 9-2x (i think?) that would sense the coolant temp and apply different levels of fan control based on the heat. it just taps into a coolant line so if i can set one of those up that would rule.

yeah josh i think its just that i dont really know my wiring and neither does he.. so its kind of this problem of finding the right pins and inputs/outputs for it which takes awhile and in the meantime it would be great to just have fans that worked.

thanks!

[Legacy777]

Here you go Zach.

I used standard relay pin number references. Meaning, that any standard Single Pole Single Throw relay you buy should have the same pin numbers. I've got a diagram on my website as well.

http://www.surrealmirage.com/subaru/tip.html#relay

Here's the diagram. Let me know if you have any questions. That coolant temp sensor sounds like a possible option if you want to get fancy, but I'd recommend sticking with just the basics for now.

http://main.experiencetherave.com/subar ... wiring.jpg

[Legacy777]

Also....for what it's worth. This diagram still works even if you decide to use the AEM to control the fans. You would just run the switched source into an output on the AEM and configure it to enable once engine coolant temp reaches a certain point.

[Legacy777]

Zach,

You try this wiring yet?

[impreza_GC8]

For the record, I was able to get my fan to work reliably bridging the power from the two speeds into a single wire that went to the fans power.

[SubaruNation]

Hey josh,

i haven't started yet

this weekend i will be tackling a ton of car stuff and ill post up here when i get it done, along with wiring questions if i have them,

thanks!

[SubaruNation]

working on it right now and trying to find a spot, ideally the cigarette lighter, that i can tie into for the other power souce. any ideas on its location in the fuse box?

[SubaruNation]

how/where can i tie into the cigarette lighter?