tub_sephiroth

I need help to wire a switch with relay to turn on my fans. Right now I have a switch but no relay and the switch and power wire gets extremely hot! Is the diagram below correct on how I should wire the switch and relay?

fcm

That is correct, although, do you need a 30A fuse? 94

suspendedHatch

May I ask why? If your answer is because your coolant switch isn't working, I'll lock this thread (hint).

tub_sephiroth

What coolant switch? I'll tell you why. It's because I'm boosted with A/C still intact. I've got a 3in intercooler blocking my radiator. It's so compact in my engine bay that my car runs very hot. The 95 degrees summer and 98% humidity that we have here in MN summers doesn't help cool the car much either. That's why I need to wire a switch to manually turn on the fans.

wrx-killer-Sti-eater

iTrader: (1)

I would check the cooling system out. The fans should come on when the car gets hot. And should stay running till the car cools down to the set tempture thats set in the ecu. Turn the fans on earliy might do the job. But if the air flow is blocked. Turning the fans on will not do anything. Did you know your fans on work while the car is sitting and not while the car is being driven. We keep this open to figure this out for a couple of post. If I were you I would step up to a better radatior that has better cooling effect. I about to go thru this twice with my itr and my gsr

fcm

I have to agree with the above, if the system is working properly your fans will be on if engine coolant temp. gets too hot, and will stay on until it's back to normal, if this is not happening, [fans staying on] then there is a problem, probably the coolant temp. switch.
Do the fans come on when the engine gets hot?
Have you checked the thermostat?
Blocking the rad and A/C condenser with an intercooler will limit are flow whether fans are on or not, a better fix would be a bigger rad, dual or triple core.
And if you still want the fan control, you do not need a relay just trigger the relays that control the fans, both use a ground to trigger. 94

tub_sephiroth

Cooling system checked. Even went as far as new head gasket. I did upgrade to a Koyo radiator. It helps a lot but I still need my fans on constant, even when driving, I'm not getting any air flow to my radiator.

fcm

As posted above if the system is working the fans, [or at the very least the rad fan] would be on all the time, if engine coolant temp. is above normal, if that's not happening then I can't see how the system "checked".
If you still want the switch, all you need to do is supply a ground trigger to the condenser fan relay, both fans should come on, if only the condenser fan comes on, supply a ground trigger to the rad fan relay, use diodes to isolate the relays.

If you want it to be automatic use the 12V+ 2nd ign. free pin on the under dash fuse box to trigger a relay that supplies a ground to the condenser and rad fan relays, if the ign. is in run, the fans are on. 94

wrx-killer-Sti-eater

iTrader: (1)

But we are going to come into anothor problem. If there is no air flow how is the fan going to pull in air. This is going to overheat the fans and blow fuses. Or blow a relay. If your going to do it the relay way I think it will be better to make it on its own circuit. Make sure it not at all attatched to the fan switch. Whats the make and model on the fmic and the car.

nsxxtreme

Boosted cars heat the water up much faster then a normal car. I had this problem in my Integra as well. With the fans always "on" its a lot harder to heat the water up to begin with. By the time the fans would normally clicked on the heat has already gone way up.

But you should be able to keep the car from overheating. Try using a thermostat that opens sooner. I remember replacing mine.

tub_sephiroth

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by wrx-killer-Sti eater &raquo;</TD></TR><TR><TD CLASS="quote">But we are going to come into anothor problem. If there is no air flow how is the fan going to pull in air. This is going to overheat the fans and blow fuses. Or blow a relay. If your going to do it the relay way I think it will be better to make it on its own circuit. Make sure it not at all attatched to the fan switch. Whats the make and model on the fmic and the car.</TD></TR></TABLE>

It's an 01 integra GSR. The fmic is made by precision.

suspendedHatch

Running the fan all the time will eat several hp from across your entire RPM band in addition to the problems already mentioned.

First make sure your OEM setup is working properly as everyone has stated. When the temp gauge reaches a certain temp, the fan should come on until the temp drops down.

Is your OEM radiator shroud intact?

I would get a high efficiency radiator and a high efficiency slimline fan.

Another thing you can do if your climate permits is run more water in your water/coolant mixture. Redline watter wetter might not be a bad idea.

If you're having coolant temp problems, then no doubt your oil is running hot also. Adding an oil cooler will extend your engine life.

tub_sephiroth

Ok, I wired the relay up exactly the diagram in this link and my car wouldn't start. I got power, but when I turned the key, the engine wouldn't turn at all.

https://honda-tech.com/zerothread?id=1487828

fcm

Where did you get power from, for #87 and #85?

What do you mean, "I got power"?

Does the cluster "light up" when you turn the key on to run, can you hear the fuel pump prime?

Do the car lights and horn work? 94

tub_sephiroth

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by fcm &raquo;</TD></TR><TR><TD CLASS="quote">Where did you get power from, for #87 and #85?

What do you mean, "I got power"?

Does the cluster "light up" when you turn the key on to run, can you hear the fuel pump prime?

Do the car lights and horn work? 94 </TD></TR></TABLE>

Positvie from #87 was coming from battery and #85 was ground wire to switch. Positive from switch was to the fuse box under the dash. From my understanding, #85 flows right to #86, correct? And since #86 is connected to ground, #85 going to the switch should be ground, then I would need a positive source to switch.

Or is #85 to switch suppose to be positive, even though #86 is going to ground?

What I meant by power was that cluster lights up, stereo works, etc. but engine wouldn't turn (like a dead starter).

fcm

The relay is wired properly, it makes no diff. if ground is on #85 or #86 as long as you supply 12V+ to the other one.

If you have power everywhere else other then the starter then it is either the starter output from the ign. switch, the starter relay, or clutch interlock switch, [standard] the gear position switch, [auto], or the starter motor or solenoid.

Try this, with a jumper wire, [12ga or so] jump from batt. pos.(+) to the solenoid input on starter motor, unplug the solenoid trigger lead, [thinner of the 2 on the starter motor] and supply 12V+ to the terminal, Caution make sure car is not in gear, [auto or standard].

Let me know what happens, and if car is an automatic or standard transmission. 94

suspendedHatch

What do you mean your car wouldn't start? Your radiator fans have nothing to do with your starter. You must have blown the main battery fuse.

I can't understand what you're saying but that diagram makes sense. Did you verify the power from the fuse box with a multimeter? What did you tap into?

Instead of the switch from the fusebox, wire 85 directly to the black/yellow wire in the ignition harness.

tub_sephiroth

Ok, got it to work using the diagram in the link. He had the wire from switch to 85 being ground. It's suppose to be positive.

fcm

Does that mean the car now starts? 94

tub_sephiroth

Yes, I don't know why but I had the relay mounted to a screw where I mounted the 89 ground also and this cause the car not to start. When I removed the relay from the same mounting area as the 86 ground, then the car started. I don't know why mounting the relay to the same screw as the 86 ground would make a difference since the relay is covered in plactic.

I don't know if I'm making sense, but everything works fine now. Thanks.

fcm

Well if your car is a 5 speed, and you somehow "disturbed" the clutch interlock switches ground, the car would not start. 94