2006 Kodiak 450 4X4 overheating

[BeauHymel]

New here, I am having trouble with my bike overheating. The temp light is working but the fan will not run. The fan will only run 

with the ignition in the off position (Key removed).   Not sure how this is possible. Also having electrical problems and it will ruin a battery (if not 

disconnected) about every 3 months. Any help/ideas would be greatly apricated. Thanks in advance

Edited November 3, 2022 by BeauHymel

[Gwbarm]

Sounds like the thermostat that turns the fan on may be bad.

[Mech]

If you go up the top of the page, click on "more", choose service manuals, and then in the new page that opens, on the right and down a bit choose yamaha, you'll find a manual..

Have a read.. It doesn't really sound like the sensor to me.. not with it only going with the key off.. If you find the right book for your bike and let me know which manual it is I'll have a look at the wiring diagram and see if I can spot anything.

[davefrombc]

If you bought that quad used and this has been happening almost right off, it might be someone has messed up the wiring to the fan. It seems to me from your description that possibly the hot wire is going directly to the fan  and the ground is switched by the relay.  Fan stays off until the sensor calls for it to  run at temperature  but the ground is switched off by the relay. When the key  is turned off the relay switches to  normal off position and in doing so  actually grounds the fan  so it'll run.. As  Mech says , there should be a wiring diagram in  a service manual  covering your machine in the download sectio n to help  you trace down the gremlin..

[Mech]

Oh that's a good thought Dave..  

[BeauHymel]

Not enough post to download yet

[Mech]

Manuals are available to download elsewhere.. Some you can read and search one page at a time online which is handy if you have limited or slow data/internet. Handy too to verify it's really for your model before you download..  But keep posting.. and you'll get one here.

Your bike is water cooled right ? And does it have belt drive, or a solid trans with five speeds, and if belt, how many forwards speeds does it have ?

I'll see if I can find the right manual and have a look.

[Mech]

Do you know the full model designation  ?  ymf450***  What are the *** ?

[Gwbarm]

Not sure if yours is wired like this, but the few water cooled units I have worked on have a thermo switch on the radiator that turns the fan on and off as needed, if you bypass this switch the fan will only run with the key in the off position, that's my reasoning for thinking the thermo switch is bad. Now if yours has a relay like Dave suggested that may be different. 

[Mech]

Ok.. I had a look at what I hope is the right manual, and I'd be checking the key switch's operation.

[BeauHymel]

2006 YAMAHA KODIAK 450 4WD  YFM45FAV

[Mech]

I've looked at a couple and they both show the key switch having two power in and two power out, both  working in parallel. One power out feeds the fan only, and the other power out feeds all the rest.

I'd guess the switch needs pulling to bits.. one of the slides playing up.. I'd say. But check it with a gauge before you pull it off and to bits.

[BeauHymel]

Thanks, I check in a few days, the bike is at the deer camp. To answer other questions.

The bike was purchased used, but 10 years ago. Started having issues 2 yrs ago with battery going

bad after only 3 months, killed 3 different batteries. Checked for parasitic amp draw and showed none.

Changed key switch and then RECTIFIER & REGULATOR with no luck. Installed a battery disconnect and

had no issues with battery since. Don't know if the fan coming on was killing batteries or not. It was recently 

I noticed the fan coming on with key off. I need to figure out how the fan is getting power and ground with 

key off and not with key in the run/on position. Sorry for long post just giving some history.

 

Also the bike is a 2006 Yamaha Kodiak 450 belt drive IRS YFM45FAV with no modifications

Thanks again.

[davefrombc]

I think Mech answered the power source to the fan  with key off.. There are 2  power source in and out on the key switch,  so  likely the second circuit is the one that powers the fan in  key off .. I would suspect the fan sensor is faulty since It would appear to me the second power source on the key switch is to provide constant power to that sensor to power the fan when the motor is still  hot  after shut down.  When the motor  is below fan  triggering temperature it should remain off no matter which circuit is powering it .  Check the output of the fan sensor with the motor  cold there should be none if the fan is powered directly through it , and if  there is a relay the fan sensor triggers,  check that relay for it  being failed on ( points fused closed) delivering power to the fan constantly.

[BeauHymel]

I hope to check this when I get the bike home. Just don't ever remember the fan running with key off.

I think I would turn the key back on till the fan stopped when warm. I hope to find better questions and answers when 

I have it home. Thanks again

[Mech]

Here's the diagram. I've looked at a few and they all seem the same. If the key is off the fan circuit shouldn't be connected to anything. Even a short to power in the fan power wire, (which could keep the fan running), wouldn't make it not work when the key is on.

2004.bmp

[Cj Winds]

The problem lies with the aftermarket ignition key switch that was replaced, find an oem key switch

[Gwbarm]

Its very possible aftermarket switch is not wired the same you might switch some wires around and find the right circuit

[BeauHymel]

I will give this a shot

[Krominator]

I have seen this happen a lot with cheap aftermarket ignition switches......It may have been replaced at some time before you bought it......Might want to check that.......Just an idea.

[BeauHymel]

Thanks, busy with work but I hope to check soon