I need someone to point to a website or tell me how I can wire up the fans with a toggle switch. I'm doing to be drag racing soon and I don't want to have overheating problems. Also I am planning on taking the "not used button" on the center console (next to the rear defroster) and turn that it my switch for the fans. That will give me even more of a stock look with performance! :D Thanks.

TTT

I am very interested in this also. Thanks

http://www.hmp.net/slowse-r/diy/fans.html

That's a pretty nice walkthrough. I wouldn't recommend using a tap like that blue one that he used. You'd be better pressed to solder your wire lead in and wrap the connection with electrical tape. If you are going to use a tap use a 3M t-tap, they make a better connection. I would also use a more weathertight fuse holder that uses a regular blade type fuse. Also, unless all that is on that circuit is the fans, I wouldn't necessarily trust that the rating of the fuse in your block is going to be the right size for just running the fans. The closer the fuse amperage is to the actual amperage of the fans the better. I would use a DC current meter to clamp over the fan wires to see how much current just the fans pull. When I do this to my car, I am going to use a relay and the switch will only operate the relay. That should keep the switch from failing due to possible higher current running through it than it is rated for. If anyone wants more help let me know and I'll draw you up a diagram to do it the way I've mentioned.

wow.. sorry to bring back an old thread.. but do you still have that diagram in mind?

And he said...."YOU SHALL LIVE AGAIN!" Bringing back the dead here. What are you looking for exactly?

And he said...."YOU SHALL LIVE AGAIN!" Bringing back the dead here. What are you looking for exactly?

The link does not work. Do you have it saved?

this is very easy. Just attach a wire from the battery to a toggle switch in the car. From the toggle switch to the Fan on the Right side, if looking at the car from the front. It will turn both fans on, dont ask me how but it works. Just leave the fans connected with the factory connections, but splice the power wire you just made into the power wire of the factory connection.

ahh okay.. but what about the part that toolapcfan says about using another relay to lighten the load on the existing relays? is that necessary?

I scrapped the old instructions, there were things I didn't like that I resolved, try these:

Things you’ll need are:

1 – SPST (single pole, single throw) switch. I would go with an illuminated one.
1 – SPDT (single pole, double throw) relay.
~ 15’ of 18 gauge wire. You could get two different colors if it makes wiring things up easier. 18 wire is small but sufficient since the current draw we will be dealing with will be marginal, well below 1 amp.
5 – 22-18 gauge (red) ¼” fully insulated female quick disconnects.
2 – 14-16 gauge (blue) ¼” fully insulated female quick disconnects.
2 – 22-18 gauge (red) ¼” fully insulated male quick disconnects.
1 – 14-16 gauge (blue) ring terminal (you’ll have to decide what size the ring needs to be depending on where you’re going to ground it).
1 – 22-18 gauge (red) 3M wire tap.
1 – ##-## gauge (color) 3M wire tap.
The taps I'd use look like this:
http://www.imagestation.com/picture/sraid97/pa46fb50bb4050aaeaf58df66ce63f907/fa147872.jpg

~ 10 – 6”-8” cable ties.


Normally I would recommend soldering the wiring, however since the wires you will be tapping into are so small and current is so low, taps will work fine and be much easier to install or uninstall at a later date if needed.

You can refer to the diagrams while reading the following so that things make sense. The GA16DE ECU is the same as the SR20DE ECU in regards to the fan relay trigger wires that we are looking for. You can also see two different diagrams depending on whether your switch is illuminated or not. First you should get to your ECU harness behind the center console on the floor under the dash. If you refer to the ECU diagram you can get an idea where the wire you’re looking for is located. The wire you want to tap for a manual transmission car is the solid blue wire in terminal position #9. If you have an automatic, then you want the blue with a black stripe wire in terminal position #10. Use a red 3M wire tap to tap into this wire. Then connect this wire to relay terminal #87. If you’re doing this to a car other than a ’93 Sentra, then you’ll want to get wiring diagrams or a factory service manual to find out which wire from the ECU goes to the fan relay(s) in your car. This is the wire that the computer grounds to operate the fan relays, and is the wire you want to tap into to ground through your switch. This wire can be found by looking at the ECU foldout in the back of the FSM. Next you’ll need to tap into a keyed power source so that the switch only operates the relay when the key is in the ACC position. Although I would ordinarily suggest that you run a wire to the positive battery terminal to do this, since the relay only draws 1.5 amps of current and will only be operating when the switch is thrown, tapping into an existing wire in the car should be relatively safe. The best wire I’ve found to do this is the white wire with a blue strip that goes through your ignition switch. Rather than tap into the wire near your ignition switch, I would do so behind the fuse block under the dash. There’s a clear/white two wire connector that you can release from the back of the fuse block on the bottom left rear of the fuse block that has the white wire with a blue strip and a brown wire with a red stripe. It's harness E46 if you want to find it in a factory service manual Again, these colors are only certain for a ’93 sentra. Tap into this wire with a wire tap and run a wire from this tap to the #86 terminal on the relay. If you used an illuminated switch, then you’ll want to run a wire from the switch to the #86 terminal on the relay as well to power that light. You can twist both wires together and crimp them together in a blue quick disconnect that will connect to the relay. Now we need to connect the grounds. Run a wire from the switch to the #85 terminal on the relay and another wire from the other side of the switch to terminal #30 where you’ll twist the wire to another wire and crimp into your quick disconnect that will go on the relay. Then ground the wire from there and you’re done.


Here's the ECU harness position diagram:

http://www.imagestation.com/picture/sraid49/p9b76f5fa4f33e7550ed9eaccae6702b4/fcb3e01c.gif

Here's the Illuminated and unilluminated switch diagrams:

http://www.imagestation.com/picture/sraid98/p8373de969fa772d43ea0d43cef336157/fa04d93c.jpg http://www.imagestation.com/picture/sraid98/p8f4d6bb3c2c4a385523f8f839ce0bd58/fa04d93a.jpg

i did notice that my switch got warm after awhile, so the switch controlling the relay is probably a better idea. But mine is hooked up exactly as I stated and it works fine, although I recommend getting a switch with a light so you dont forget to shut it off. I killed my battery *** I left the damn things on.

its a brown wire witha white stripe I just splice into this from a toggle and ran it straight from the battery.

Yeah, but you're bypassing the relay, there's no need to do that, the relay is always hot, it just needs to be grounded to operate and you can do that from inside the car using the ECU wire that triggers the relay by grounding it. I don't understand why people want to do stuff the hard way. To each their own I guess.

it still comes on when ever it needs too on its own, I just have a switch that sends it 12 v whenever I want it to. What makes a 1 wire splice "the Hard Way" It took me 3 min to hook up":rolleyes:

Yeah, but you're bypassing the relay, there's no need to do that, the relay is always hot, it just needs to be grounded to operate and you can do that from inside the car using the ECU wire that triggers the relay by grounding it. I don't understand why people want to do stuff the hard way. To each their own I guess.

ahhh.. that sounds much easier.. i was looking at the wiring diagram.. is that the blue wire on pin 9?

I dunno, there's nothing wrong with how you did it, it justs seems to make more sense to me and is a lot easier to just trip the relay like the ECU does and not have to run a wire to the battery, which you then have to fuse because you're sending power directly to the fans. Not to mention you had to run wiring through the firewall into the car to your switch, which takes a lot longer than 3 minutes. There's many ways to do it, I just think tripping the relay is the easiest, safest and most correct way to do it. When you essentially say, "Do it this way." I kind of shake my head, because I'm very carefull about these kinds of things, because although I could give a person various configurations that would work, fi they ever have problems down the road and possibly have an electrical fire, then I don't want to be the one who told them to do it that way. Tripping the relay is no different than how it would work if the ECU were doing it, so I know without a doubt that it'll work and it'll be safe. It's sort of like when people ask about hooking up an aftermarket tach over at the Nissan Forums. Damn near everyone that replies says, "Drill a hole in the firewall and tap into the coil wire...." and again, I shake my head, because there's an abandoned OEM tach wire that's easy to get to that's inside the car that a person can tap into to run to their tach. Why run wires or add fuses and circuits when Nissan already did it? That's all I'm saying.

ahhh.. that sounds much easier.. i was looking at the wiring diagram.. is that the blue wire on pin 9?

That's right. When I initially responded to this post last year I hadn't looked at the wiring diagrams as closely as I did this time around, which is scarey really.

I updated the info to allow more flexibility options.

I updated the info to allow more flexibility options.

Damn you seem to know exactly what you are talkinga bout... I am about to rig a switch up to my radiator fans as well because I bought the fal-220 with the adjustable thermostat and a/c relay which I should have just gotten everythign from you because I can't figure out how to wire this up, its frustrating me. They are on all the time thats why I need to get aswitch hooked up.

Rob: Kinda off topic but do you know how to wire up the black box witha million connections taht flex a lite sends you with their fans to the sr20 relay stuff so it works?

BTW Rob where did you learn all this electrical stuff? You just a genius in that area because I have no idea what I am doing....

Thanks, I try my best. When I decided to add power windows and locks to my truck, which they were never options for, install an alarm and stereo, I had to learn about relays, wire sizing, and fuses to make that all happen. I also had to learn about polarity reversing 5 pole switches. So I'm pretty much self taught. Then when I took an AC electrical class and had to learn ohm's law that really increased my knowledge. Numerous alarm, keyless entry, and remote starter installs later I think I've got the hang of this stuff. When I did that cluster swap article for NPM I really learned a lot about reading wiring diagrams, and how to use the FSM (which is full of flaws and inconsistencies mind you). I just get excited about automotive electrical stuff I guess. I sold power windows for a 4 door Ford Tempo to a kid in Michigan once, I had pulled them from a junkyard for my wifes car but never installed them. To help the guy out I figured out how he needed to wire the stuff up, all without wiring diagrams or a FSM for that car. It took me a decent amount of time, but I drew up wiring diagrams and install info and he put the stuff in and it worked without a hitch. I was quite proud of myself for that. Well, he did cut his finger tip off but that was his fault, not mine.

About your fans, yeah, you should have bought Spal fans from me, I barely mark them up so they're a lot cheaper than the FAL fans in most cases. ;) If you can provide me with the wiring info that came with your fan relay I can help you out. I assume it came with a thermostat that operates the fan relay? If you can scan or take a digital pic of the instructions I can help you out.