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Discussion Starter · #23 ·
Wow what a thorough but simple explanation! Thank you for that. I will check and swap the fuses next and if those are good then I will undo the splice and check from there.
 

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Discussion Starter · #25 ·
Okay so weird thing is happening now. I haven't undid the splicing nor have I swapped fuses. The only thing I've done was swap the relays and the fan wiring. Now the car started to have both fans come on when I turn the AC on and when it gets up to temp 203 F, both fans will turn on. When it is up to temp and I turn the AC on both fans stay on. So, it's better than before but it still seems wrong. Unless these fans don't have individual settings and just both come on and off.
 

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Now that's why it is better to have your 2 single speed fans wired to different speeds.

For the OEM dual speed fans both come on at low speed when the aircon is switched on so that air is drawn through the condenser. Then high speed comes on for extra cooling when the radiator temp is too high.

So having one fan connected to low speed of fan 1 and the other fan connected to high speed of fan 2 would give you similar operation.

Sent from my SM-G900I using Tapatalk
 

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Discussion Starter · #28 ·
If by testing you mean with a multimeter, then no I haven't since I don't have one. I only swapped them around and was getting the same result so I thought they were good. I don't know how they both started to come on at the same time now. I also can't tell if they are blowing at a high or low speed. I'm assuming high since it's pretty loud. Could that mean the relay that's for both fans could be bad since they're both just coming on high? I'd rather not have to do any rewiring if I don't have to. I don't have any splicing tools either.
 

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Since your SPAL fans only have 2 wires then they are only single speed.
The OEM fans were dual speed which is why there are 4 wires from the harness.

There are no different voltages between low and high speed. It is only 12V on one set of wires or the other.

Your fans will only run at a single speed but since the OEM harness switches the 12V from one set of wires (low speed) to the other set of wires (high speed), this is why the original owner spliced the 2 sets of wires from the harness together, otherwise your fans would only run when the aircon was on or when the engine was too hot and not both.

So having one fan connected to Fan 1 low speed (yellow and black wires) will have it run when the aircon is on and having your other fan connected to Fan 2 high speed (Blue/black and yellow/black wires) will have it run as additional cooling when the engine is too hot.
 

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Discussion Starter · #30 ·
Ah I see now. So the fans are working as they should due to how they were spliced in. If I do the wiring like that, will the low fan stay on when the high fan kicks in? And if I do that, there will be left over wires? Also, any guess as to how they're both suddenly working?
 

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My guess is they are both suddenly working because with the relay swapping and wire disturbance, that some poor connection has been activated.

Looking at the circuit diagram, output 37 turns on Fan relay 1 for low speed of both fans and output 27 turns on both Fan relays 2 & 3 for high speed of both fans individually.
What I am uncertain of is if the low speed output stays on or turns off when the high speed output is activated.
If you connect your fans as I suggested in my last post then you might see fan 1 turn off when fan 2 turns on. This would show you that the outputs switch over so then all you need to do is connect both low and high speed wires to fan 1 so that it runs in both cases. This will be simply connecting the Green/Yellow wire to the Yellow wire and connect the White/Blue wire to the Black wire (as I think it is now).
If the first fan stays on when the second starts then you know both outputs stay activated together and you will be good to go.

Yes you will have spare wires left over.
Either the high speed wires for fan 1 (Green/Yellow and White/Black) and the low speed wires for fan 2 (Green/Red and Black) or if you need to connect fan 1 to both speeds then just the low speed wires for fan 2 (Green/Red and Black) will be spare. Just tape them up separately (not together) so they are isolated from touching anything or each other.
 

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Discussion Starter · #33 ·
I'll take a look into doing that Revhead. Thanks for all of the help and explanations! And mirrortints, yes I'm all for cooling down the engine bay as much as possible, especially in this heat
 

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Discussion Starter · #34 ·
So, there is definitely a bad/loose splice. When I turned on the AC again yesterday, only one fan turned on. I pressed down on the electrical tape where the splice was with my fingers and the second fan turned on. So that splice just needs to be redone.
 

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It’s best to solder those connections. With all the vibration in that area, splicing tends to come undone.
 
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OK, I was having the same problem. When moving fine when in traffic air kicks off. I just checked the fans and they both work even the high speed works but for some reason the fans just turn off all of a sudden. I waited and they turn on and off not sure why.
 

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Discussion Starter · #39 ·
Reviving my old thread rather than creating a new one. I have another related issue with the fans. When I have the ac running for awhile in either stop and go or idle at some point the compressor and or fan shuts off and warm air starts to blow. I then see coolant temps get above 203 and even with the ac button off, the regular fans won't come on until the temp gets to 221. This never happens with the ac off. The fans will always come on right at 203 and shut off around 188. This issue has the fans shutting off at 210 instead of going back down.

This doesn't happen every time I have the ac on either. Other times I'll be idling with it on and it will stay around 192 ish. So how come the fan shuts off when the compressor shuts off and why doesn't come back on at the right temp?

I should also note I had the spal fans replaced with the mishimoto fans and shroud and had them wired by an actual professional. The soldering on the spal fans was done by the previous owner and were not well done. This issues has happened with both fan set ups.
 
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