OK, I'll try that.. Is it definitely that switch then though?

And Neil - every time I see your sig pic, it makes me daydream about how cool it would be to party with a kangaroo

 

No its not "definitely" the switch but its way the most likely cause.
If grounding the wire that goes into the switch causes the fan to come on, i'm 99.99% sure its the switch.
I never say 100%.

I haven't had any experience with repairing these particular switches but it is something I have done with other thermo switches on other equipment.

If you want to party with a roo, get your butt down here and I'll give a few of em a call.
Parties at my place are good so I think they will turn up.
Gotta be careful though.
3 beers and they start dancing.
Nothing fancy mind, mainly the pogo.
I put on some punk music and they just jump up and down on the spot.
Funny as hell but it sure makes a mess.

 

Thanks for this. My KLX650 came with a toggle switch already and that stopped working. My guess is the toggle switch went bad but this helps in ultimately fixing the the real problem.

 

I'd try replacing the fuse, looking at the wiring diagram I'm inclined to think the fuse is in the ground circuit.

 

I didn't know that the fan circuit was independently fused?
Where is this fuse?

Oh and another thing.
Try freezing the switch.
Ya just never know?

 

Yeah - I don't think there is a fuse for the fan.. Though the manual says fuse, I'm thinking they are meaning the relay..

I just got back from vacation and I haven't rode in almost two weeks. I think today I'm going to put it all back together, and throw a switch on it. Maybe I'll save that one for the winter slumber!

Neil - sounds like a great time!!! The wifey and I have been dying to go over there.. Maybe one day.

 

At the least the switch will be easy. Just remove the sensor wire, add some wire to it, add switch, and add a ground wire.

Good info about the groundings. Now I have to test mine. Never had the temp light come on, and the fan hasn't come on in a long time.

 

CORRECTION its the right radiator switch that controls the fan
Sorry.

 

What happens if you just swap the wires from the left switch to the right switch and vice versa? Doesn't the left switch only control the overheat lamp. Swap the right hand wire to the left switch and the fan will come on again just at a slightly different temp' I suspect.

Opinions!

Fan switch range: Off to On 94oC-100oC, On to Off 93oC-90oC.

Temp warning light range: Off to On 107oC-113oC, On to Off 103oC-106oC.

My point is, do you know how hot the coolant is while riding? You don't! The only indication it's getting hot is when the Temp' warning light comes on. If you've fitted a switch to the fan, that's when you turn the fan on. May as well automate the function IMO.

 

I put the little toggle on yesterday. The red light didn't come on at all the whole day so I didn't really get to try it.. But it was high 80's and muggy - so when I got to the tight stuff in the woods I just flicked it on and left it on.

Cooler is better than hotter on any machine!

I'm OK with the switch for now. Maybe over the winter or something I can find a new rad switch cheaper.

WestOz - I thought about the same thing. Only bad thing I could think the motor would be at that "red" point, then the fan would go on for a split second, cooling it a bit, then off, then on, off, on, off.. I dunno.. Just seems like it'd be too hot for comfort. With the switch I can flip it on when I know I'm going to be putting through some tight stuff.