AC Fan Wiring

[FWD98GST]

Here's the deal... I hooked up a 11" spal fan for the AC. I noticed that there is one live wire which is a blue one and the ground is black... First of all, is there a high or low setting for the AC fan? My setup for the fan seems to be low and doesn't really blow really hard... I have two other blue wires that I didn't connect... Should I be utilizing those two blue wires at all to make the fan go faster? Or this is it.. It's just a one speed setting for the AC fan?

Thanks..

 

[Omega]

yes the speeds are part of the motor but the speeds are determined by the voltage going to the motor, otherwise there wouldnt be 3 separate power wires going to the fan for different speeds, which is why i mentioned the relays, because some relays are used to raise voltage or lower voltage.....................if the motor determined the speeds itself there would be one power wire

I am not so sure about that. Each relay still delivers 12V, it just goes to different windings in the motor for the different fan speeds.

 

[Tarantula]

I am really curious on how to make my stock fan run on straight HIGH! I don't want to wait till it gets to 242F to run high. That made sense that maybe the fan speed is determined by the voltage going through the different windings inside the motor housing. Its true that 12V is 12V across all the relays.

 

[Omega]

Relay's don't raise or lower anything. They are an electricly activated switch. No more, no less.

They could be used to supply the fan with a 6, 8 or 12V supply, but then the fan would only need two wires since the supply voltage would vary. The lower voltage from the usual ~14.4V in a car, would be lowered by resistors, not a relay.

The reason you used relays to activate your door poppers through the alarm is because the relays within the alarm couldn't handle the current draw. The voltage output from the alarm compared to your secondary relays is pretty much the same.. perhaps off by 10% but nothing special.

Spidey,

You have to pick the right set of windings in the fan. Once you have that figured out, wire the lo and med wires to that wire also and you will be good to go.

 

[99gst_racer]

Tarantula - Theroretically, if you wired the HIGH motor winding to the LOW relay, your fan would kick on the high speed everytime you hit 210* F. If I had stock fans, I would test to verify this, but I dont, so I cant.

 

[olmytsi]

I got another quick fan question guys. Does the a/c fan ever come on while the a/c IS NOT turned on?
I removed my a/c but i have a slimline fan laying around that i would like to put in in the a/c fan spot. Will i need to turn the a/c switch on to make that fan come on or does it come on when the coolant temp is sky high?

 

[n0c7]

I got another quick fan question guys. Does the a/c fan ever come on while the a/c IS NOT turned on?
I removed my a/c but i have a slimline fan laying around that i would like to put in in the a/c fan spot. Will i need to turn the a/c switch on to make that fan come on or does it come on when the coolant temp is sky high?

If your A/C is removed, I would just wire the second fan into the first one although I don't know how this would affect voltage load.

 

[62-1gsx]

I got another quick fan question guys. Does the a/c fan ever come on while the a/c IS NOT turned on?
I removed my a/c but i have a slimline fan laying around that i would like to put in in the a/c fan spot. Will i need to turn the a/c switch on to make that fan come on or does it come on when the coolant temp is sky high?

how do you got your coolant slim line hooked up right now? does it work good, does it come on and stay on.....i cant get mine to work....

 

[Omega]

OMEGA----
i get what your saying it makes sense the way you explained it, but what about the way i used to to run my led.....the output on the alarm was 2v, the led would only run on 12v...so i had to run the signal wire from the alarm to the relay along with another 12v source to get the scanner to operate like its supposed to.....

i dont know i just want my fan to work so i can drive the dam car!!!!

It's still a switch Think about what you said. You took the 2V output from the alarm to activate a 12V from somewhere else. The 2V switched on the 12V which the LED was connected to. It didn't take the 2V and bump up the voltage to 12V.

Now that I think about it, my attempt to wire all of them together didn't work either. It could be that there is only a LO and MED, but when both are activated, you get HI... but anyway. Do some checking. Make sure you have not blown any of the fan fuses. they are the big suckers and expensive to replace. Make a temp 12V supply for the fan. Go through the pinouts with the temp supply to figure out what the inputs are on your own car. Get back to us and we'll work from there.


n0c7:

That would work but it has some serious potential to fry wires, relays and fuses. Run a fuse protected wire from the battery in to a relay. Tap into the power wire for the first fan and run it to the relay trigger... don't forget the ground. Finally run the output of the relay to the new fan. You get nice high voltage from the battery (use 12 -14 gauge wire) for max flow from the fan and you protect the OEM wiring. My SPAL fan sounds like a friggin' turbine with a nice dedicated battery supply.


olmytsi:

I think the info is at the begining of the thread about when and which fan comes on. I am pretty sure that the AC activates the HI AC fan relay. Connect the fan to that wire. Yes, the AC button will now activate that fan.

 

[99gst_racer]

olmytsi - Post #25 should answer your question.


Just for the record, I have both of my fans wired together and they both come on full force when the LOW relay is triggered at 210* F. I dont have any relay problems, nor do I blow fuses. I have had it wired like this since earily May, and I have yet to experience any problems.

 

[Tarantula]

Tarantula - Theroretically, if you wired the HIGH motor winding to the LOW relay, your fan would kick on the high speed everytime you hit 210* F. If I had stock fans, I would test to verify this, but I dont, so I cant.

Thats exactly what I was thinking!!! Today I went outside and hooked a multimeter to find what wire turns on the rad. fan. Well the blue wire is the feeder to the low speed. I also looked to see which relay turns on the fans at 210 and above...Its the LO relay. With AC on the other fan yurns on as well. Turns out that with the AC running both fans run off the LO relay. I hooked into the relays like the mod in the VFAQ and it does run both fans but what happens is the Rad. fan runs slower and the AC fan Even slower. I figured that if blue is LO on the fan, than Yellow is Medium and Green is high. (Green usually means GO like in traffic lights ) When the car cools down I'm going to pass 12V into each of the three wires. And going to ground the black wire. I'm going to see if the fan blade turns faster between the different wires. If so, I think I'm going to wire the fast (Hi) wire to the power wire in the connector.

 

[Tarantula]

Well I just went outside to see if changing the wire colors make the fan spin faster. NOPE I ran ground to black and ran 12V across each of the remaining colors on the plug. The blue wire spins the fan like it normally does. The Green wire, which I thought might be the fast or Hi spun the fan exactly the same speed as the blue wire, and the yellow did nothing. Did not spin the fan blades. I even tried joining the blue and green wires to see if it spins faster and no!!! the same.
Tried the same with the AC fan. Ran ground to black and 12V to the other colors. Same results, the fan does not spin any faster with any of the other options.

 

[olmytsi]

olmytsi - Post #25 should answer your question.


Just for the record, I have both of my fans wired together and they both come on full force when the LOW relay is triggered at 210* F. I dont have any relay problems, nor do I blow fuses. I have had it wired like this since earily May, and I have yet to experience any problems.

Thank you, i should have read thru it

 

[62-1gsx]

It's still a switch Think about what you said. You took the 2V output from the alarm to activate a 12V from somewhere else. The 2V switched on the 12V which the LED was connected to. It didn't take the 2V and bump up the voltage to 12V.

, i guess that is what i did huh? stupid me oh well im gonna try hookin it up agaain tomorrow, check those stupid fuses again....thanks man

 

[Tarantula]

I found it!!!! I found how to make it run on high without modifying relays!!!!!
It really does run at a significant higher speed!!! Heres what I did. I waited till the fan turned on. Wired the high relay to ground. (pin 1 on the hi relay) I immediately noticed that the fan started to run higher. I took off the high relay ground now that I know the speed of high. So I took a multimeter to see which wires were supplying voltage to the fan. We all know that theres 4 wires to the fan. BLACK YELLOW BLUE GREEN.
I placed the multimeter to measure the blue wire. It only had 9 Volts.. So I was like what? I than measured the green wire. It too was running volts. It was running 13volts. Both wires were running voltage.
I took a jumper wire and joined both the green and blue wire while the fan was running and it went to high speed!!!! Left it like that and waited.
The fan shut off at 199. I still waited. When the fan turned on again it went on high!!!!!! instead of regular low!!!

With the Hi relay mod both fans turn on just like the Vfaq Lo relay mod. I found the mod HERE
Theres another mod and to jump the ECU wire to ground to run both fans on high with a switch. The Switch mod is here!
There finally a happy ending!!!

 

[Tarantula]

A picture is worth a thousand words I just used those quick connects and a piece of 16 AWG red wire. and jumped the blue and Green wire together. Fan turns on at high speed everytime the ECU turns on the fan. Lots of people say keep the stock fan, well this is another reason to keep it.
The first time I joined the two wires with 12V and thats why it did not work. It needs the signal from the two other wires that connect with the plug for it to work.

 

[olmytsi]

how do you got your coolant slim line hooked up right now? does it work good, does it come on and stay on.....i cant get mine to work....

My main (coolant) fan is stock.

 

[olmytsi]

I wired up my slimline fan the way you guys said to: both grounds to the ground on the fan and both hi and lo speed to the power on the fan and it works so thanx alot for all the input.

 

[Mooseknuckle]

I followed Tarantula's directions for the fan mod today, and it worked great. Fan kicks on at high speed whenever it normally came on. Thanks!