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Old 10-01-2013, 08:27 PM   #1
Hart_Rod
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Question Electric fan question

My electric fan setup has a high RPM fan and a low RPM fan.

Question #1: which fan is considered the primary fan as far as the computer is concerned? high or low RPM?

Question#2: which fan should I connect the trinary switch to? High or low RPM?

Thanks in advance!
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Last edited by Hart_Rod; 10-02-2013 at 10:22 AM.
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Old 10-01-2013, 11:28 PM   #2
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Re: Electric fan question

Question 1 low
Question 2 high
My first fan on temp is 200 low speed second fan comes on at 215 high speed.
In reality when the fans come on they just run full speed. I don't have anything that pulse modulates. That trinary will turn on the fan when ever the compressor is activated. You want as much air moving across the condensor especially when stopped. Just the way I will be wiring mine when my a/c goes back in.
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Old 10-02-2013, 02:18 AM   #3
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Re: Electric fan question

That's the same way mine is setup. Driver side on mine is low, passenger side is high side. I did set mine up just like factory, with a relay controlling each fan and a controller relay also. I still need to set up my trinary switch, but I understand some precaution needs to be taken when hooking up to the high fan. If done incorrectly it will supposedly cause the ECM to throw a code of some sort. I'm still researching the correct way to make it work.
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Old 10-02-2013, 09:10 AM   #4
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Re: Electric fan question

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Originally Posted by Daaaanz67 View Post
Question 1 low
Question 2 high
My first fan on temp is 200 low speed second fan comes on at 215 high speed.
In reality when the fans come on they just run full speed. I don't have anything that pulse modulates. That trinary will turn on the fan when ever the compressor is activated. You want as much air moving across the condensor especially when stopped. Just the way I will be wiring mine when my a/c goes back in.
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Thanks for the info, that's how I plan on hooking it up. The crazy thing is, my fans actually run at different speeds. It is very noticeable in the amount of air they pull through.


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That's the same way mine is setup. Driver side on mine is low, passenger side is high side. I did set mine up just like factory, with a relay controlling each fan and a controller relay also. I still need to set up my trinary switch, but I understand some precaution needs to be taken when hooking up to the high fan. If done incorrectly it will supposedly cause the ECM to throw a code of some sort. I'm still researching the correct way to make it work.
Shawn
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I think you will be very pleased with the dyno results and consider money well spent. Keep us updated.
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Old 10-02-2013, 09:37 AM   #5
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Re: Electric fan question

Here's what someone posted and the correct way to wire the trinary and I agree stay away from the relays that the comp uses. This should prevent setting any codes.
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Old 10-02-2013, 09:39 AM   #6
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Re: Electric fan question

Here's what someone posted and the correct way to wire the trinary and I agree stay away from the relays that the comp uses. This should prevent setting any codes.
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Old 10-02-2013, 09:41 AM   #7
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Re: Electric fan question

Sorry for double post maybe a moderator can fix this
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Old 10-02-2013, 10:18 AM   #8
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Re: Electric fan question

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Sorry for double post maybe a moderator can fix this
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Roger. That's the schematic I was going to use. So use the low RPM fan with the primary trigger (from the computer) and the high RPM fan with the secondary trigger (from the computer) AND the trinary switch?.

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Old 10-02-2013, 11:26 AM   #9
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Re: Electric fan question

Yes that relay on the left is the stand alone that you will wire in. The positive wire that feeds the fan from that relay will just tie into the same positive wire That is currently feeding your "high speed" fan other words splice them together. This will demand the fan to come on any time the compressor is on. If for some reason the engine needs more cooling the computer will activate the high speed fan anyways and override the trinary in between let's say the compressor cycling. These two circuits will work together. Hope that makes sense.
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Old 10-02-2013, 12:17 PM   #10
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Re: Electric fan question

Ok guys. Let's discuss this for a minute. My understanding is that the trinary switch will only kick on the fans when the pressure gets above a certain level. So for instance if your driving down the freeway the fans won't run just because the AC is on. If that is so, is there a way to run the trinary switch to the ECM so that when the pressure hits it will tell the ECM to turn on the fans? Seems like the system is already built into the ECM, it just needs a signal from the trinary to turn on the fan when pressure gets too high. Am I missing something? Here is how I wired my fans, minus the power train relay.
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Old 10-03-2013, 01:54 AM   #11
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Re: Electric fan question

I agree with the idea that there should be a way to send an "A/C demand" signal as well as a signal from the trinary switch to the ECM and have it control the fans. Isn't this how the factory cars work? I had to add another relay and tap into my #2 fan's power wire to get it to work.
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Old 10-07-2013, 11:42 AM   #12
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Re: Electric fan question

Well, here is one reason mine wont work... Could someone be so kine as to explain how/what a trinary is?? I am just using a 30 amp relay to hook mine up but it wont work and this is probably why. Also, I don't have A/C for now.

Thanks for any help.

Ben
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Old 10-07-2013, 11:46 AM   #13
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Re: Electric fan question

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Well, here is one reason mine wont work... Could someone be so kine as to explain how/what a trinary is?? I am just using a 30 amp relay to hook mine up bot it wont work and this is probably why.

Thanks for any help.

Ben
The trinary switch is a part of the A/C system that senses pressure/temp to operate the compressor and cooling fans
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Old 10-07-2013, 12:25 PM   #14
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Re: Electric fan question

So I shouldn't need that at the moment correct?
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Old 10-07-2013, 01:26 PM   #15
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Re: Electric fan question

You need a trinary switch so that when you turn the AC on AND HEAD PRESSURE REACHES A PREDETERMINED LEVEL, the fan will turn on. Trinary switches don't just turn on the fan when you turn the AC on, which is where much confusion lies.
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Old 10-07-2013, 03:21 PM   #16
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Re: Electric fan question

I didn't want to get that deep into it, but jorgensensc is absolutely correct. There are good tutorials available on youtube and such if you want to read up on it. If you don't have A/C don't worry about the trinary switch.
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Old 10-07-2013, 03:30 PM   #17
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Re: Electric fan question

Hey buck! I hope you don't think I was trying to call you out. That was not it at all. I just keep seeing elsewhere that people keep saying the trinary makes the fan come on when you turn the AC on. I also see where people wire the fan to come on with the AC, but when your on the freeway cruising you probably don't need the fan on and running it can possibly damage the fans. That's why it's important to run the fan of the AC head pressure.
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Old 10-07-2013, 03:40 PM   #18
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Re: Electric fan question

No worries I understood your point, I guess I figured I could just state it generally. Everything you are saying is spot on!
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Old 10-07-2013, 09:37 PM   #19
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Re: Electric fan question

Cool, thank guys! and yes, I forgot to mention I was not running A/C at the moment.
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Old 10-11-2013, 06:39 AM   #20
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Re: Electric fan question

Where would you wire a 2-wire temp switch off the radiator in at on this diagram?



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Here's what someone posted and the correct way to wire the trinary and I agree stay away from the relays that the comp uses. This should prevent setting any codes.
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Old 10-11-2013, 06:04 PM   #21
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Re: Electric fan question

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Where would you wire a 2-wire temp switch off the radiator in at on this diagram?
The short answer is you don't! That diagram is showing how to add an additonal relay to isolate an A/C trinary switch from the PCM's fan control lines. The reasoning is that it prevents the PCM from throwing trouble codes like you would get if you just tied the trinary switch and the PCM control lines together. If you're using a temp switch, then there is no reason for the additional relay as shown in the diagram.

If you're using a temp switch, then I assume you aren't using the PCM to control the fans? Do you have A/C? Do you have one fan, two, or a dual speed single fan? If you have 2 fans do you want to run 1 for low and both for high or run both fans at half speed for low and both at full speed for high? If you provide some information about what you're trying to do and what parts you have, I could point you toward a schematic to do what you need.
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