# Fan switch 08+ Brute Force



## Tempsho

I am looking at installing a fan switch on my 09 Brute Force.

Has anybody hooked up a switch on the 08+ brutes so that you can control the fan manually and also still have the stock temp sensor kick in if needed?

The water temperature sensor on the 08 and up Brute is different than the 07 and down models. The temperature sensor isn't an on/off (open/closed) type switch. It changes resistance depending on the temperature of the coolant and I think it feeds that resistance into the ECU which then controls the fan relay by grounding the yellow wire.

I think if I splice into the yellow wire coming off the fan relay and switch it to ground it would essentially do the same think the ECU does.

Any input on this would be nice!


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## blue beast

if you hook it up like the how to it will work both ways,when you want it to and when the temp sensor tells it to .follow the instructions ..but i would solder and seal up any conections that i made if i were you ..i just dont trust the little wire splices...here are 2 threads that will help you i read through both of them before i got started

http://www.mudinmyblood.net/forum/showthread.php?t=641
http://www.mudinmyblood.net/forum/showthread.php?t=5278


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## BrutemanAl

yes read through the how to's on this topic , I did alsoread through both and it was a great help , I wired mine =right to the thermostat , 1 wire on each wire coming off the thermostat and it works like a charm  I would recomend soldering everything though , does not take long for dirt and crud to get into the wiring and the toggle switch starts acting funny , works , then doesn't work , then works lol . Iended up taking mine apart and soldering it all .


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## NMKawierider

Tempsho said:


> I am looking at installing a fan switch on my 09 Brute Force.
> 
> Has anybody hooked up a switch on the 08+ brutes so that you can control the fan manually and also still have the stock temp sensor kick in if needed?
> 
> The water temperature sensor on the 08 and up Brute is different than the 07 and down models. The temperature sensor isn't an on/off (open/closed) type switch. It changes resistance depending on the temperature of the coolant and I think it feeds that resistance into the ECU which then controls the fan relay by grounding the yellow wire.
> 
> I think if I splice into the yellow wire coming off the fan relay and switch it to ground it would essentially do the same think the ECU does.
> 
> Any input on this would be nice!


As read the circut, I believe you are correct, the yellow from the ECU has to provide the common for the relay as 12V is supplied by the main fuse through the fan breaker for both the fan and the relay. Very different from the 05s-07s. Other control circuts use a low voltage control but this one looks to be 12v. I guess ground it and see....lol


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## Tempsho

I took the easy route and ran a wire from the positive on the accesory port, to a switch, and then to the positive on the fan wire. (BL/R) Works perfect! I could have tapped into the yellow wire on the relay but that would have involved running longer lengths of wire. Pics to follow to show where I mounted my fan switch.


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## wyo58

Yellow to ground should have done the trick. Thats what the ECU is doing to the circuit to make the fan come on.


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## Tempsho

Here's the pics as promised. Nice and clean looking, almost factory. Next up will be an oil cooler for both machines!


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## blue beast

i think im gonna replace my switch now ..i like the way that looks..


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## vogie

I am going to do this mod for sure, my question is since I will be grounding the circuit how will I get the light on the switch to come on? Run the light terminal to positive on the battery? and when the switch grounds out it will put the light on?


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## Tempsho

The switches are cheap on ebay.

http://cgi.ebay.com/5-Led-Light-12V...019?pt=LH_DefaultDomain_0&hash=item2eb5fbddc3

They also have ones with a rubber cover (added protection against water)

http://cgi.ebay.com/5X-12V-DC-WATER...=AU_Car_Parts_Accessories&hash=item415715fed4

If you want the switch to light up you'll have to tap into a positive wire. I found tapping into the auxilary wire (cig lighter) was less work than trying to tap into the yellow wire on the relay.





























Vogie, I would suggest tapping into the positive wire on your accessory plug. Much easier, less wire to run and it lights up if you ground the ground prong on the switch!


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## vogie

WOW thanks for all the info, I assumed you just reverse what you would normally do for a + system for a - system, I will tap into the yellow wire at the relay and then run it up to the pod hopefully I can hook up to that accessory wire I already have my winch tapped into it.

I bought the switch locally from an autoparts dealer it was a Grote brand name for $4.00 part#82-2132 for the specific green light but you can get about 3 or 4 other colors which the end number changes. Says to drill a 15/16" hole.

Again thanks a bunch for the info I will do this hopefully tonight!


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## Tempsho

If you want it to light up, you would run a positive wire to the ground prong on the switch, tap into the yellow wire on the relay and hook that up to your *Load* on the switch and then ground then *Line (or source).*



















So yeah, essentially you'll be wiring it up backwards. 

In my opinion, if you're going to be tapping into the + accessory wire anways, you might as well just wire it the way I did. That way you don't have to tap into the relay wire. (less soldering, less wire to run, and less chances of a tapped wire failing because of moisture or corrosion) The only extra load on the accessory circuit will be the light on the switch which will only be a few milliamps.


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## vogie

Tempsho said:


> If you want it to light up, you would run a positive wire to the ground prong on the switch, tap into the yellow wire on the relay and hook that up to your *Load* on the switch and then ground then *Line (or source).*
> Hopefully this helps you.


Yup makes perfect sense and is exactly what I will do thanks again.


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## wyo58

Tempsho make sure that the fuse for the acc. is a 10amp just like the breaker for the fan normally.


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## Tempsho

Good call. Off hand do you know what size of fuse is for the accessory plug?


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## wyo58

The wiring diagram says it's a 10 amp as well so should be ok!


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## vogie

Tempsho, my mind works overtime so I appologize for all the questions but if the system is indeed a ground out to turn the fan on how would you hooking into the positive wire make the fan turn on? 

Supplying positive power to an already powered wire shouldn't turn the fan on without somehow being grounded or maybe I am mis understanding what you did.


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## Tempsho

The yellow wire is only being grounded to complete the circuit on the relay. There isn't a constant positive going to the fan. The fan only has power when the relay is energized.


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## vogie

K, got it thanks I will probably do what you did looks much easier and less wiring lol.


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