Hey, I’ve been having some issues with my stock cooling system. I just changed the engine harness and plan to hook my cooling fan switch back up. But I’m not sure if I wired the fan right.
Here’s the situation. I have 2 slim fans wired together somewhat like a subwoofer when u run wires parallel. I was wondering if this is the proper way to do it or should I run them in series? I was tryin to use the stock power source, but I’m not sure if it is going to split the current when going to both fans. They do seem to run slow when I have them hooked up, so I was wondering what would be the best way to give them both efficient power? Also I will be doin this without ac. really need help with this cause it’s gettin hot and I’m worried about overheating my new motor. thanks in advance
MM&Y of car?
Did your car have A/C but no longer does and you want to use both fans for the rad?
If so, I would not use the stock rad fan power lead, [fuse 12 - 15A,] unless the current draw on your “slim fans” is 7.5A or less, [each].
So the question is, what is the current draw of the fans?
The stock wiring may not be able to carry the current needed by both fans, with the stock rad and condensor fan they are wired separately, the rad fan has a 12V+ constant going to it and the ground is supplied by the rad fan relay, triggered by the ECTS, the condensor fan has a constant ground and power is supplied by the condensor fan relay, triggered by the A/C pressure switch [both the rad fan and condensor fans run when A/C is on].
Best bet would be to wire one fan as the rad fan using stock wiring, wire the second fan as the condensor fan using stock wiring, then disconnect the condensor fan relays coil leads, at the relay, [black/yellow and blue] connect the black/yellow to a 12V+ ign. source, it can be the black/yellow on the rad fan relay.
Connect the blue to the yellow/green at the rad fan, [from ECTS] that way both fans will turn on when engine coolant temperature hits about 190 degrees F, [off the ECTS]. 94
Currently tryin to wire these from scratch without any factory wiring. I found a diagram i will post so u guys can give opinions. I thought about using the underhood fuse box as the power source and ign on these relays. Will this work? And I also plan to use factory rad fan switch on thermo housing.
LMK what u guys think about this idea. Will wiring it this way tear the relays up when running since it will be around 13v? or does the relay adjust this current to 12v? I’m in need of dire help here. it’s hot as hell in GA.
And thanks for your comments. This car came without factory ac and I added it, but plan to boost it later so I didn’t want to wire the a/c fan way. plus my factory wiring for these fans suck.
Yes the wiring will work, make sure you use the ECT switch, [rad fan switch] and not the ECT sensor to trigger the relays.
If your G2 is USDM you will loose the oil temp. fan control.
Unlike the CDM G2s the USDM G2 has an EOTS, [engine oil temperature switch] that supplies a ground to the RFCM, [radiator fan control module] if engine oil temp. reaches about 226 degrees F, turning on the condensor fan, even if ign. switch is off.
This is not the case, if when you added A/C to your car you did not install the RFCM, in which case your not loosing anything.
With that said, I would maybe install the EOTS, [threaded into back of engine block] and have it trigger a pr. of relays that would turn on the fans even with ign. off.
Same wiring as your linked diagram but with #85 comming from the EOTS and #86 from a 12V+ constant, [unswitched] source.
That along with a turbo timer will insure the engine stays cool.
I assume you are removing the A/C when you turbo the engine, and you will not be using the A/C once you wire in your two “slim fans”, this is important, without a condensor fan A/C head pressures can go through the roof, [in excess of 400PSI, leading to poor cooling and compressor damage and most likely rupturing an A/C line, condensor or evaporator, makes a hell of a mess with PAG/Ester oil sprayed all over the place. 94
thanks again for your insite cause I’m far from an electrician. I was thinking that the way I have it wired the coolant switch would keep the fans on after the car is off until the rad fan switch shuts off. I had it wired that way before but I had it straight off the battery which was killing the ect everytime after driving for a while. But it did keep the fans on with the car off which I liked a lot. I might try the way u suggested with the oil pressure switch, but I already have it T’d off for the ls/vtec line.
I currently have the 2 10a fuses under the hood removed that aren’t used as a power source for each fan. Then right before the relay I split this in 2 going to 86 and 30. That way its always powered and just controlled by the fan switch. I just have to ground it today so I’ll see if this works out. And ya I’m ditching a/c soon again anyway.