Bypassing radiator fan relay??

[eddyspaghetti]

Hi fellow dsmrs, quick question.
Recently my driver side fan went out, now...i turned on the a/c and both fans turned on, so I am assuming the fan itself works?
I've been thinking of bypassing both fans so they can both be turned on via a external switch.
Before I do this, can this be dangerous to my car in anyway? Even assuming I wire everything 100% correct?
Any advice would be much appreciated

And what voltage of wire should I be getting for this project?

1997
mitsubishi eclipse
gsx
automatic transmission

 

[Patchez_]

the same gauge wire as what runs the fans should work i feel like its 12-14 gauge wire but you are also going to have to put a relay between the new switch and the fans to separate the low and high current components. i would consider finding a switched power source in the fusebox and use it to power your fan relay so you eliminate the idea of a switch, reason being if you forget to turn on the switch could overheat. if you want advice i would not cobble up my car like that i would replace the fan relay or temp sensor causing the problem.

 

[eddyspaghetti]

the same gauge wire as what runs the fans should work i feel like its 12-14 gauge wire but you are also going to have to put a relay between the new switch and the fans to separate the low and high current components. i would consider finding a switched power source in the fusebox and use it to power your fan relay so you eliminate the idea of a switch, reason being if you forget to turn on the switch could overheat. if you want advice i would not cobble up my car like that i would replace the fan relay or temp sensor causing the problem.

Would you happen to know where I could by the relay? Because I am going to need 3 new ones right?
Would I be able to get the relays and the temp sensor from a 2g GS or a RS? Or does it have to be strictly a GST or GSX?

Any help would be much appreciated, thank you

 

[Vegas Smith]

People usually add relays and increase wire gauge when they switch to slim fans due to fear of overrunning the stock wires/relay. You can buy the relay at any autostore and the temp switch at rockauto. Do a search on Google for dsm slim fan install and you'll find some great threads. I would suggest not adding an external on/off switch as already mentioned. Add a switch means you have to manually turn the fans on every time you drive the car.

 

[ryshinazy]

If you do end up going with manually powered using a switch I would make sure you have a good temp gauge to avoid overheating as stated above.
That's what I ended up doing when my fans went out. I got a generic 5 pin relay from the auto part store and ran a whole new set of wires for the fans and they are switch powered. I also installed a glowshift temp gauge so I can monitor the coolant temp and turn the fans on and off as needed

 

[eddyspaghetti]

People usually add relays and increase wire gauge when they switch to slim fans due to fear of overrunning the stock wires/relay. You can buy the relay at any autostore and the temp switch at rockauto. Do a search on Google for dsm slim fan install and you'll find some great threads. I would suggest not adding an external on/off switch as already mentioned. Add a switch means you have to manually turn the fans on every time you drive the car.

Yeah to be honest I didn't really want to go that route.
I've been searching on eBay for the fan relay and I can't find any, what should I be searching under?
Is there an exact name that I should be typing in? Maybe the relay number? Any help would be much appreciated thank you

 

[eddyspaghetti]

If you do end up going with manually powered using a switch I would make sure you have a good temp gauge to avoid overheating as stated above.
That's what I ended up doing when my fans went out. I got a generic 5 pin relay from the auto part store and ran a whole new set of wires for the fans and they are switch powered. I also installed a glowshift temp gauge so I can monitor the coolant temp and turn the fans on and off as needed

Also, I'm going to need three relays right?
How much do these relays usually cost?

 

[pauleyman]

why don't you fix the cause of the problem and let the factory system do it's job.

 

[GST with PSI]

If you want both fans to run together, I would simply use the factory fan circuit to control a relay. Then, use that relay to control the ground side of the circuit for both fans. Here's what I would do:

2G Passenger side (radiator) fan wires are:
lo positive (+12V) = white/black (white with black stripe)
lo negative (goes to ground) = black
hi positive (+12V) = white/blue
hi negative (goes to ground on M/T, switched on/off to ground by the 5th radiator fan relay LO2 on A/T) = blue/green

So, I'd wire the 12v wires for both the high and low fan circuits together. Then, wire those to the relay coil so that anytime either the high or low circuit sees power, it will trigger the relay.

Wire both of the fans' positive directly to 12v battery. Wire both of the fans' negative to the relay. Make sure you select the appropriate relay based on the amperage your combined fans will pull (30A-40A would probably be a safe bet).

@luv2rallye can comment/check my work, as I'm not terribly familiar with the 2G electrical system.

I basically have my fans set up this way on the Galant. You can get the relay from basically any local parts store. Again, just ensure the relay is rated to handle the required amperage of your two fans combined.

P.S. This only works if your factory fan circuit is functioning properly. As the others have already told you, you need to fix the problem with that before you do anything else.

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[GPLaserRS]

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https://www.summitracing.com/parts/...h-automotive&gclid=CMD03InL49QCFVlXDQodwMYKHw

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[1990TSIAWDTALON]

Nice drawing Brett! Good write up.

I would use a 40 AMP not a 30 AMP Relay, for good measure. 2 fans on one 30 amp relay MAY be drawing on it hard is why I suggest that. They just handle the load a bit better and not burn out.

Also, Simple relay diagrams just posted for Electrically Challenged folks a couple days ago:

http://www.dsmtuners.com/threads/simple-4-pin-relay-diagram.512623/#post-153652678
or

http://www.dsmtuners.com/threads/simple-5-pin-relay-diagram.512624/#post-153652679

 

[1990TSIAWDTALON]

Your relays should be here:

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[eddyspaghetti]

Also, I'm going to need three relays right?
How much do these relays usually cost?

Why don't you read the above comments?

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https://www.summitracing.com/parts/...h-automotive&gclid=CMD03InL49QCFVlXDQodwMYKHw

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This isn't the relay, can you please point me in the right direction for this specific sensor I'm looking for? Or anyone? Because I'm havin

Your relays should be here:

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No, I meant where I would be able to buy the 3 relays. For some reason the guy from summit racing and myself weren't able to find the relays to buy, any help?

 

[1990TSIAWDTALON]

Let me go look at my sons WRECKED 97 Spyder.....

 

[eddyspaghetti]

Let me go look at my sons WRECKED 97 Spyder.....

Wrecked? Man, hope he's ok

 

[eddyspaghetti]

Can I get any relay as long as the part number says
Mr122409 and 12v ?

Because it has another long number that doesn't usually match with other relays, which is this number 7115A12A

For example, like these relays, the have the number mr122409 & they are 12v,
But that 3 row of numbers isnt the same as my relay

 

[GST with PSI]

Dude, just pull one relay from the fuse panel and plug it into the one in question. That's probably the easiest way to check and see if one is bad. You can also bench test it with a 12v source.

If your fans are running when you activate the A/C, the relays aren't the issue anyways.

 

[eddyspaghetti]

Dude, just pull one relay from the fuse panel and plug it into the one in question. That's probably the easiest way to check and see if one is bad. You can also bench test it with a 12v source.


If your fans are running when you activate the A/C, the relays aren't the issue anyways.

Well sir, if you're so sure that the relays isn't the issue, would you be so kind to share as to what might be the issue???....

 

[1990TSIAWDTALON]

The temp switch that tells the fans to turn on. That could be in the radiator or on the thermostat housing. It would have been the FIRST thing that I checked since the fans work when demanded to with the A/C switch.

 

[eddyspaghetti]

The temp switch that tells the fans to turn on. That could be in the radiator or on the thermostat housing. It would have been the FIRST thing that I checked since the fans work when demanded to with the A/C switch.

Just to be sure, this is the sensor you are referring to, right?
And is their any way of testing the sensor other than replacing it to see if it's gone bad?

 

[GST with PSI]

i turned on the a/c and both fans turned on

Based on the diagram below, your driver side fan probably wouldn't function if the relay was bad given your statement.

I'd start by checking pins 20 and 21 to ground to ensure the ECU is operating the circuit. Use the diagram below. It's pretty easy to check for power and ground at the critical points in the circuit, such as the ECU, relays, fans plug, etc. This is fairly easy stuff.

@luv2rallye needs to chime in here.

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The temp switch that tells the fans to turn on. That could be in the radiator or on the thermostat housing. It would have been the FIRST thing that I checked since the fans work when demanded to with the A/C switch.

No, there's no temp switch on the 2G like there is on the Galant and 1G cars. The ECU controls the fans.

 

[eddyspaghetti]

Based on the diagram below, your driver side fan probably wouldn't function if the relay was bad given your statement.

I'd start by checking pins 20 and 21 to ground to ensure the ECU is operating the circuit. Use the diagram below. It's pretty easy to check for power and ground at the critical points in the circuit, such as the ECU, relays, fans plug, etc. This is fairly easy stuff.

@luv2rallye needs to chime in here.

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No, there's no temp switch on the 2G like there is on the Galant and 1G cars. The ECU controls the fans.

Maybe something I should have mentioned before and let me know if this has nothing to do with this problem, but my car wouldnt start after I would park after driving.
It would turn on, but wouldn't crank.
I would have to mess with the wires under the steering wheel column.
Could it be that I might have moved something wrong under there?

Because come to think of it, I never had a fan problem until I started doing that

 

[GST with PSI]

Use the diagram below

The answers you seek can be obtained by using the diagram. You'll notice the "ignition switch" is one of the components pictured.

As much as I'd like to help, nobody is going to be able to spoon feed you the answer here. You're going to have to get a multimeter out and test various parts of the circuit. There's literally no other way to identify the actual problem. If you can tell us which parts of the circuit do/don't have power/ground, we could help more. Absent that information, any other help that is provided would simply be guess work.

 

[eddyspaghetti]

The answers you seek can be obtained by using the diagram. You'll notice the "ignition switch" is one of the components pictured.

As much as I'd like to help, nobody is going to be able to spoon feed you the answer here. You're going to have to get a multimeter out and test various parts of the circuit. There's literally no other way to identify the actual problem. If you can tell us which parts of the circuit do/don't have power/ground, we could help more. Absent that information, any other help that is provided would simply be guess work.

Well for starters, I'm not asking any one to feed me with a spoon, I'm only asking questions so that I can figure what's going on.
Second, if you knew anything about common sense, you would of realized that I asked and mentioned the part under the driver panel because of the fact that in that area lies the ignition switch right?
Now, I don't know how well you're memory is, but it's written in the previous comments stated above by me mentioning the driver panel, correct?
Hold tight...ill give you a minut to process that...
Ok, where we're we.
Now... the diagram you showed me has the ignition switch on the diagram itself, you see where I'm going with this?

One last thing, If you're going to be rude...dont bother trying to (supposedly) help someone looking to get out of a certain issue with his or her car by helping..and then insulting them.
Pick one, either you're a nice person or not you can't be both sir.
I'm sure you didn't come out of you're mother's vagina already knowing how to work on a mitsubishi eclipse. You were once new to this as well.
The whole point of this is to help someone out, so that THAT person can help someone else in trouble, so that THAT person can help out another person with his or her issue etc... get it?

Good day

 

[Vegas Smith]

The guy wrote you an essay including pictures of the Factory Service Manual, yet he isn't helping you. Good luck with that.