Issues with wiring Mishimoto radiator fans.
09-05-2009, 04:46 PM
#22
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When we were working on mine, we marked which clip went to which fan.
I have two issues:
1. I am still f'in overheating. I realized that so long as the AC is off, I can idle forever without overheating. However, AC goes on, I give it 15-20 minutes before my temp gauge starts to climb. The fawked up part, it doesn't matter if I am idle or going 75 on the freeway, 15-20 minutes with AC and I overheat.
2. I am not sure if it is my AMS Radiator or the Mishimoto Fan Shroud, but the passenger side bracket would not line up. I should have checked it on my old stock radiator, but it was painful enough getting the damn thing in there without removing my SC.
The wiring seems to still be working for me. I do need to go in there and clean it up a bit with some heat shrink and reducing the massive amount of slack I have left in the wiring.
My only other 'complaint' is, that I realized yesterday that the CFM rating on the 12" Mishimoto fans is ~900 each. My old FAL fans were rated to 2500 for the pair. I am hoping this isn't what is causing my AC overheating issue, if it is, I may have a slightly used Mishimoto Fan/Shroud available for sale soon.
Oh, and I installed my new Weapon R Coolant Overflow tank because the sun cracked my stock one. Shiny.
I have two issues:
1. I am still f'in overheating. I realized that so long as the AC is off, I can idle forever without overheating. However, AC goes on, I give it 15-20 minutes before my temp gauge starts to climb. The fawked up part, it doesn't matter if I am idle or going 75 on the freeway, 15-20 minutes with AC and I overheat.
2. I am not sure if it is my AMS Radiator or the Mishimoto Fan Shroud, but the passenger side bracket would not line up. I should have checked it on my old stock radiator, but it was painful enough getting the damn thing in there without removing my SC.
The wiring seems to still be working for me. I do need to go in there and clean it up a bit with some heat shrink and reducing the massive amount of slack I have left in the wiring.
My only other 'complaint' is, that I realized yesterday that the CFM rating on the 12" Mishimoto fans is ~900 each. My old FAL fans were rated to 2500 for the pair. I am hoping this isn't what is causing my AC overheating issue, if it is, I may have a slightly used Mishimoto Fan/Shroud available for sale soon.
Oh, and I installed my new Weapon R Coolant Overflow tank because the sun cracked my stock one. Shiny.
My first problem is they said they would offer the fan shroud with out the fan for the people who installed the 12" prior to their release, then they changed their mind on that one. Next if they lied about the the performance of the fan they are intentialy defrauding customers with faulty information. Im going to email them to see if they will explain any further.....
Never mind I am going to file any ways. I just saw on their site the fans are 724 ft/min Errr not a happy customer. I'll keep this thread abreast of whats going on.
As what Im seeing now a friggin 10" Mr. Gasket cooling fan has 950CFM. So I definatley want answer on this subject from mishimoto.
EDIT: From what I've seen so far the stock fans have been noted at 500cfm but through unreliable sources. With this the two Mishimoto 2 fans sould put out 1448cfm thats a 50% increase in flow. There should be significat cooling if thats the case. It seems Mishimoto is on the lower end of cooling capacity for aftermarket fans.
http://cgi.ebay.com/ebaymotors/12''-...04219008r24980
These 12" fans move over 2X more air (1250cfm each) at 1/3 the price ($28 each). If you wanted to go with something less EBAY then Summit has 16" fans the same price as the Mishimoto 12" fan but has just over 2000 CFM each. Mishimoto lists the radiator fanshroud spec at 28.5" X 18.7". This should fit the at least 2-14" fans or 1 16" for the primary and 12" for the secondary. Together you will flow over 3000 CFM which is 100% more than the mishimoto 12" combo.
ERRRR... I keep looking and typing and get ALOT of other fans that pop up. Hell look at Summit. They have an 26" X 18" dual 13" puller fan system that will move 4000cfm and it has pressure relief ports to flow even higher levels at high speeds. http://www.summitracing.com/parts/DE...7/?image=large . I just need to check the amperage draw for the stock circuit this one pulls 50 amps.
For the big-*****-trucker of cooling Summit has: http://www.summitracing.com/parts/PR...0/?image=large
Its a little more expensive but flows 5,900 with dual 13 inch fans and only pulls 19 Amps wich is well within the wiring limits. It sits at 28" X 18" and is 4.5" thick so within stock size.
All these can use the plastic retainers to mount them with out any issues. Im honestly thinking about making this a seperate thread to push the word out.
Last edited by punish_her; 09-05-2009 at 06:15 PM.
09-07-2009, 07:03 PM
#23
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I wired things up just as you suggested, you are correct when I turn the car on when at temp 1 fan runs. When I turn on the AC however the other fan does not turn on.
What could be the problem. The other fan does come on when the car gets hot and I can hear the speed change as well.
What could be the problem. The other fan does come on when the car gets hot and I can hear the speed change as well.
09-07-2009, 08:17 PM
#24
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Thats odd. The speed shouldnt change because the the full voltage per leg is going to each fan individualy. I would have to see your wiring to see whats goin on but from the sound of it you may have some of your wires off.
Double check the continuity on all your connections. You may have a bad ground on fan 2. Also, double check the voltages on your conectors.
Unplug fan 1 and fan 2
Check continuity between both grounds and the chasis as well as to each other.
Turn on the car but DO NOT START IT.
Check the voltage on fan 1 and 2 with out the A/C on.
Check the voltage on fan 1 and 2 with A/C on.
Start the car and check the voltage on the fan 1 with A/C off.
Check voltage on fan 1 with AC on.
!!!!!!!!MAKE SURE YOU DO NOT LET IT RUN MORE THAN A MINUTE OR SO.!!!!!
Once the car has cooled down, Plug in fan 1
Start the car.
Check the voltage on fan 2 with out the A/C on.
Check the voltage on fan 2 with A/C on.
Check the Voltage once the car is up to temp with AC off.
What you are looking at:
There should be continuity between both grounds, the chasis, and each other. If not you have a bad ground.
Fan 1 should have a constant voltage and there should be no increase in voltages even with the A/C on.
Fan 2 should have no voltage with the AC off and car at low temps. With the AC on there should be the same voltage as fan 1 on fan 2. If you have voltage with the car running with out the AC on and low temps then you have crossed wires some where.
The reason for this is the constant on (circuit 1), is isolated to fan 1. The depend circuit (on w/ AC or high temps) is isolated to fan 2. It should only come on with either of the two triggers. The voltage on fan 1 should be the same as fan 2 with car on and AC on.
There should not be speed changes in either fan.
Let me know what you find.
EDIT: For those of you who are running into issues with overheating it may be better to wire the fans up like factory. So 2 into one on both legs of the connectors so you will have a high and low circuit connected to the blue wire and grounds to the black. This will leave both fans on all the way. I am thinking about doing some tests to see if you can force the mishimoto's to be vairable speed like the factory ones.
Nosurftoday what brand of fans are you running?
EDIT EDIT: FYI for refrences or searches. Cooling fan circuit runs from battery voltage and share a 40Amp breaker for 3 relay's (pg-26). Looks like relay's 1 and 3 control each fan and relay 2 controls the temp dependant/AC on circuit. Relay 1 and 3 use a single leg of a DPDT relay wich turn on both fans. The DPDT relay 2 applies an additional 12 -15V to each fan when on (controlled by AC/temp switches). This would be a max of 24V to each fan on high.
Double check the continuity on all your connections. You may have a bad ground on fan 2. Also, double check the voltages on your conectors.
Unplug fan 1 and fan 2
Check continuity between both grounds and the chasis as well as to each other.
Turn on the car but DO NOT START IT.
Check the voltage on fan 1 and 2 with out the A/C on.
Check the voltage on fan 1 and 2 with A/C on.
Start the car and check the voltage on the fan 1 with A/C off.
Check voltage on fan 1 with AC on.
!!!!!!!!MAKE SURE YOU DO NOT LET IT RUN MORE THAN A MINUTE OR SO.!!!!!
Once the car has cooled down, Plug in fan 1
Start the car.
Check the voltage on fan 2 with out the A/C on.
Check the voltage on fan 2 with A/C on.
Check the Voltage once the car is up to temp with AC off.
What you are looking at:
There should be continuity between both grounds, the chasis, and each other. If not you have a bad ground.
Fan 1 should have a constant voltage and there should be no increase in voltages even with the A/C on.
Fan 2 should have no voltage with the AC off and car at low temps. With the AC on there should be the same voltage as fan 1 on fan 2. If you have voltage with the car running with out the AC on and low temps then you have crossed wires some where.
The reason for this is the constant on (circuit 1), is isolated to fan 1. The depend circuit (on w/ AC or high temps) is isolated to fan 2. It should only come on with either of the two triggers. The voltage on fan 1 should be the same as fan 2 with car on and AC on.
There should not be speed changes in either fan.
Let me know what you find.
EDIT: For those of you who are running into issues with overheating it may be better to wire the fans up like factory. So 2 into one on both legs of the connectors so you will have a high and low circuit connected to the blue wire and grounds to the black. This will leave both fans on all the way. I am thinking about doing some tests to see if you can force the mishimoto's to be vairable speed like the factory ones.
Nosurftoday what brand of fans are you running?
EDIT EDIT: FYI for refrences or searches. Cooling fan circuit runs from battery voltage and share a 40Amp breaker for 3 relay's (pg-26). Looks like relay's 1 and 3 control each fan and relay 2 controls the temp dependant/AC on circuit. Relay 1 and 3 use a single leg of a DPDT relay wich turn on both fans. The DPDT relay 2 applies an additional 12 -15V to each fan when on (controlled by AC/temp switches). This would be a max of 24V to each fan on high.
Last edited by punish_her; 09-07-2009 at 09:16 PM. Reason: added service amnual fan info.
09-12-2009, 08:55 AM
#25
bump, what's the latest on this?
i have a mishimoto fan shroud sitting around, but hesitated at installing it after reading this thread a few weeks ago. looks like a bunch of the concerns have been dealt with, but i'd like to know if the wiring diagram is still working for people.
also, since you can basically install whatever fan you want after you already have a shroud, i've considered getting a 14" spal fan that will flow ~1700 cfm to replace the 12" mishimoto fan on the passenger/fan 1 side of the shroud (just cut the opening a little bigger). this will be similar to the 12" / 14" combo GTM sells for considerably more money. i know it will fit, but i'm positive that the 14" spal fan will draw more amps than the 12" mishi fan. anyone see any issues with using the wiring diagram above with two fans that draw different loads?
i have a mishimoto fan shroud sitting around, but hesitated at installing it after reading this thread a few weeks ago. looks like a bunch of the concerns have been dealt with, but i'd like to know if the wiring diagram is still working for people.
also, since you can basically install whatever fan you want after you already have a shroud, i've considered getting a 14" spal fan that will flow ~1700 cfm to replace the 12" mishimoto fan on the passenger/fan 1 side of the shroud (just cut the opening a little bigger). this will be similar to the 12" / 14" combo GTM sells for considerably more money. i know it will fit, but i'm positive that the 14" spal fan will draw more amps than the 12" mishi fan. anyone see any issues with using the wiring diagram above with two fans that draw different loads?
Last edited by - bigc -; 09-12-2009 at 08:59 AM.
09-12-2009, 09:00 AM
#26
I've been using the wiring diagram punish_her has posted for a few months. Thanks again punish_her.
I've also considered the exact same thing as you, where I would replace the fans with some SPAL ones (30102038, 1640CFM) but you still have to tackle the wiring the same way since the the SPAL also only have one set of (+) and (-) wires. HTH.
I've also considered the exact same thing as you, where I would replace the fans with some SPAL ones (30102038, 1640CFM) but you still have to tackle the wiring the same way since the the SPAL also only have one set of (+) and (-) wires. HTH.
09-12-2009, 09:16 AM
#27
thanks for letting me know i'm not alone in considering this 
i figure you have to come up with your own wiring regardless of the fans you run, so why not replace 1 or both of the smaller mishi fans with Spal fans that pull more air? once you have the shroud you can strap whatever fan you want to it.
i figure you have to come up with your own wiring regardless of the fans you run, so why not replace 1 or both of the smaller mishi fans with Spal fans that pull more air? once you have the shroud you can strap whatever fan you want to it.
Last edited by - bigc -; 09-12-2009 at 09:20 AM.
09-14-2009, 10:19 AM
#28
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The shroud is a fairly universal thinf once you hve the mounting points. You can always cut the holes bigger. It looks like you can squeeze 2-13 inch fans in there or one 1-15" and 1- 12". The big thing isnot overloading the circuits.
Definately a shroud will help with the cooling though. It will give a space that will evacuate as a whole giving a better/even airflow accross the whole radiator oposed to the straped directly onto the radiator as I have it. I would prefer to get the shroud, hell or even buy a brake from Harbor freight and do one my self. Time will tell though. I want to tinker with the wiring a little bit when I get back from my vacation. Maybe even buy one of those summit fan setups I listed above.
Definately a shroud will help with the cooling though. It will give a space that will evacuate as a whole giving a better/even airflow accross the whole radiator oposed to the straped directly onto the radiator as I have it. I would prefer to get the shroud, hell or even buy a brake from Harbor freight and do one my self. Time will tell though. I want to tinker with the wiring a little bit when I get back from my vacation. Maybe even buy one of those summit fan setups I listed above.
09-23-2009, 03:46 PM
#29
did anyone ever develop a wiring diagram that would turn on only 1 fan when the low temp trigger was hit (98C / 208F), then both fans when the high temp trigger was reached (100C / 212F) and/or the A/C was turned on? the only diagrams I've seen have both fans coming on at the low temp trigger.
its probably not a big deal since there's a very small window between the low & hi temp triggers, but why have both fans running if you don't need them to.
its probably not a big deal since there's a very small window between the low & hi temp triggers, but why have both fans running if you don't need them to.
09-24-2009, 06:22 AM
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I recently installed the Mishimoto fan shroud kit in my 04 and wired it like punish_her suggested.When i turn on the car fan 1 comes on and When i turn on my A/C , fan 2 takes a while to come on.Therefore when on A/C max ,the air is not as cold as it should be.I wonder if it is due to the fans being 1 speed.I haven't driven the car yet,so i still have to test it some more. Any updates on this?
09-29-2009, 05:53 PM
#31
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I recently installed the Mishimoto fan shroud kit in my 04 and wired it like punish_her suggested.When i turn on the car fan 1 comes on and When i turn on my A/C , fan 2 takes a while to come on.Therefore when on A/C max ,the air is not as cold as it should be.I wonder if it is due to the fans being 1 speed.I haven't driven the car yet,so i still have to test it some more. Any updates on this?
When I initialy put these fans in I was hoping to eliminate the fan shroud all together. I pulls enough air for highway speeds but no where near enough for arround town driving. I would like to see how a larger 15" and 12" combo pulls with a shroud.
As for the comment about the 2 fan set up comming on independantly the wiring diagram in the beginning does just that.
09-29-2009, 06:59 PM
#32
sweet, good to know 
i'm going to install my homemade 12" mishimoto / 14" spal combo next weekend and will report back. the mishi pulls 933.5 cfm and the spal pulls 1,720. my only worry is that the different power draws between the fans may create an issue.
i'm going to install my homemade 12" mishimoto / 14" spal combo next weekend and will report back. the mishi pulls 933.5 cfm and the spal pulls 1,720. my only worry is that the different power draws between the fans may create an issue.
Last edited by - bigc -; 10-13-2009 at 07:34 PM. Reason: updated info on cfm rating
10-09-2009, 09:45 PM
#33
i wired up my fans yesterday and tested them out by plugging them into the OEM connections at the base of the radiator. the fans switch on as described above - one fan turns on at 208, the other fan comes on at +210 (both fans running). also, both fans turn on when the A/C is switched on. FYI, whichever fan you wire up with the blue & yellow wires (2 & 4, as described in post 12 & post 16) will turn on first.
With regard to the 12" mishi / 14" spal fan combo, everything turned on as expected. Actually, the spal fan is so strong it almost pulled the mishi fan into its blades since I had them both lying next to eachother on the ground!
My only concern is at the moment the second fan switches on during non-A/C operation at temp +210F, the fan that is already on slows down for about 1 second then resumes its normal speed. In my setup, the 14" spal turns on first and is the one that slows down momentarily when the 12" mishimoto fan turns on...seems to almost go down to half speed, then goes right back to pulling like a fan possessed. My guess is that is has something to do with either 1) spal fans can be run at different speeds based on the current (per their website), 2) the different electrical loads (17amps max on the spal, ???A max on the mishi), and/or 3) higher resistance created when the 2nd fan is looped in. Anyway, seems to work fine, but if anyone seems any potential problems please let me know
With regard to the 12" mishi / 14" spal fan combo, everything turned on as expected. Actually, the spal fan is so strong it almost pulled the mishi fan into its blades since I had them both lying next to eachother on the ground!
My only concern is at the moment the second fan switches on during non-A/C operation at temp +210F, the fan that is already on slows down for about 1 second then resumes its normal speed. In my setup, the 14" spal turns on first and is the one that slows down momentarily when the 12" mishimoto fan turns on...seems to almost go down to half speed, then goes right back to pulling like a fan possessed. My guess is that is has something to do with either 1) spal fans can be run at different speeds based on the current (per their website), 2) the different electrical loads (17amps max on the spal, ???A max on the mishi), and/or 3) higher resistance created when the 2nd fan is looped in. Anyway, seems to work fine, but if anyone seems any potential problems please let me know
Last edited by - bigc -; 10-09-2009 at 09:46 PM.
10-10-2009, 07:06 AM
#34
i wired up my fans yesterday and tested them out by plugging them into the OEM connections at the base of the radiator. the fans switch on as described above - one fan turns on at 208, the other fan comes on at +210 (both fans running). also, both fans turn on when the A/C is switched on. FYI, whichever fan you wire up with the blue & yellow wires (2 & 4, as described in post 12 & post 16) will turn on first.
With regard to the 12" mishi / 14" spal fan combo, everything turned on as expected. Actually, the spal fan is so strong it almost pulled the mishi fan into its blades since I had them both lying next to eachother on the ground!
My only concern is at the moment the second fan switches on during non-A/C operation at temp +210F, the fan that is already on slows down for about 1 second then resumes its normal speed. In my setup, the 14" spal turns on first and is the one that slows down momentarily when the 12" mishimoto fan turns on...seems to almost go down to half speed, then goes right back to pulling like a fan possessed. My guess is that is has something to do with either 1) spal fans can be run at different speeds based on the current (per their website), 2) the different electrical loads (17amps max on the spal, ???A max on the mishi), and/or 3) higher resistance created when the 2nd fan is looped in. Anyway, seems to work fine, but if anyone seems any potential problems please let me know
With regard to the 12" mishi / 14" spal fan combo, everything turned on as expected. Actually, the spal fan is so strong it almost pulled the mishi fan into its blades since I had them both lying next to eachother on the ground!
My only concern is at the moment the second fan switches on during non-A/C operation at temp +210F, the fan that is already on slows down for about 1 second then resumes its normal speed. In my setup, the 14" spal turns on first and is the one that slows down momentarily when the 12" mishimoto fan turns on...seems to almost go down to half speed, then goes right back to pulling like a fan possessed. My guess is that is has something to do with either 1) spal fans can be run at different speeds based on the current (per their website), 2) the different electrical loads (17amps max on the spal, ???A max on the mishi), and/or 3) higher resistance created when the 2nd fan is looped in. Anyway, seems to work fine, but if anyone seems any potential problems please let me know
keep up the good work guys
10-10-2009, 12:23 PM
#35
i'm only using one mishimoto fan, but the schematic does work. whether or not the fans will keep your engine cool depends on how much heat additional heat your tt is generating and when you program your fans to turn on. if you get an aftermarket fan controller (which would negate the use of the wiring diagram above), you can turn on your fans earlier than stock which will keep your engine cooler than it would be otherwise.
10-13-2009, 07:33 PM
#38
...My only concern is at the moment the second fan switches on during non-A/C operation at temp +210F, the fan that is already on slows down for about 1 second then resumes its normal speed. In my setup, the 14" spal turns on first and is the one that slows down momentarily when the 12" mishimoto fan turns on...seems to almost go down to half speed, then goes right back to pulling like a fan possessed. My guess is that is has something to do with either 1) spal fans can be run at different speeds based on the current (per their website), 2) the different electrical loads (17amps max on the spal, ???A max on the mishi), and/or 3) higher resistance created when the 2nd fan is looped in. Anyway, seems to work fine, but if anyone seems any potential problems please let me know
FYI, there was some confusion earlier in the thread with regard to the CFM of each Mishimoto fan. I confirmed today via phone that they are indeed rated at 933.5 CFM each, for a total of 1,867 CFM for the pair. Anyone have any new data on the CFM rating of the stock fans?
10-19-2009, 11:47 AM
#40
I installed the fans this weekend. The fans work great, but I was a little disappointed in the mishimoto fan shroud. The driver side tab had to be bent to get it to line up (i've seen this in other folks' install pix) and the passenger side tab was about 1/4" too short. It took some persuasion to find a way to install the shroud that didn't leave a big gap on either side of the shroud.
Pre-install. All connections were soldered & heat-shrunk, and the wires were wrapped in split loom once i got the fans in place.
Installed
Pre-install. All connections were soldered & heat-shrunk, and the wires were wrapped in split loom once i got the fans in place.
Installed
