Bike got really hot a couple of weeks ago up to 120 degrees and fan wasn't working. I took everything apart thermostat was sticking and while i was at it i bought a new coolant switch and also tested the fan and it works.
I did buy a cheapy china fan switch and checking the resistance it didn't even work so binned it but the funny thing was the original honda switch was reading in kilo ohms which is really high but put it back in
and fans still not working.
I ordered a honda fan switch just waiting but what are the actual specs for the switch as i can't find them anywhere and google saids no.

 

Do you have power going to fan connector? Switch connects to ground side when it reaches high-temp. But if there’s no power going into fan, connecting ground side won’t turn fan on.

 

Yep there is power to the blue black and i did put the switch spade to earth and the fan does work just can't find the specs for the switch. I ordered one for japan was the cheapest place to buy one and noticed earlier the timing chain sounds
noisy i could hear it so ordered another from japan cheaper than getting it from the uk so another thing to fiddle with.
shame its not overnight parts from japan fast n furious style

 

Surely a switch is a switch - infinite resistance when open, zero resistance when closed and dc rated for at least 15 volts.

 

Fan switch-circuit is very simple:



1. You've confirmed power to fan.
2. Confirmed fan spins when other side is earthed.

Now measure resistance of green ground-wire to chassis-earth to make sure that wire is not broken. Connect ring-connector to earth-connector on fan. Does it run?

If not, you've got broken green wire between ring-terminal to earth.

Fan-switch only connects at +105C. So have to test in pot of boiling water similar to ECT test. Might not connect due to water not hot enough.

 

not necessarily as resistance specs are different for whatever manufacturer. As i couldn't find the specs for bikes easily as i can with cars the only thing i could find was a post about 600rr on some other website quoting specs in in kilohms which seems high.

 

Thanks it makes sense that it opens at 105c as i couldn't get the new genuine one to read as water only boils to 100c so maybe the cheap one i did originally get worked. The new genuine one works now so i have a fan so no worries in traffic now thanks again.

 

Ah good job!