Thermoswitch broken

[Squishy]

Hello.

Since I bought my bandit 400 3 years ago, the fan has never turned.
Temp light turned on recently (only had 1L of cooling  ) but still the fan doesn't kick in.
So I connected the fan straight to the + leaving the thermostat out and the fan works fine.

I guess this means the thermoswitch is broken. Is this something that can be fixed or should I just buy a replacement switch. Don't think I need a new thermostat assembly..
Will thermoswitches from other bikes (cbr600f3??) fit the thermostat? Or do I need specific gsf400 switch.
With thermoswitch I mean the bottom sensor in the thermostat with the 2 wires.

Any thoughts?

Thanks

[interfuse]

If you only had 1L of coolant, the liquid might not have been making it's way up to the switch and thus not turning the fan on.

In the manual there's a test for the switch.

Mine was broken, I replaced it with a new one. I bought the GSF400 one but you could probably take the switch to a motorcycle salvage shop and match it up with one from a different bike.

The ghetto/temporary way to fix it is to wire it up so the fan is on all the time (ie tied into the lighting circuit) or controlled manually with a switch.

[Squishy]

If you only had 1L of coolant, the liquid might not have been making it's way up to the switch and thus not turning the fan on.

In the manual there's a test for the switch.

Mine was broken, I replaced it with a new one. I bought the GSF400 one but you could probably take the switch to a motorcycle salvage shop and match it up with one from a different bike.

The ghetto/temporary way to fix it is to wire it up so the fan is on all the time (ie tied into the lighting circuit) or controlled manually with a switch.

Well I've got another b400 - and the fan turned on quite soon. I've never heard the fan on my b400 in 3 years, even on very hot days.
I don't want it to be on all the time since it's not that warm here usually and the b400 runs too cool by itself already.
Yeh the manual says I have to put the switch in a pan with oil and connect it to a circuit tester. But what else can be broken if the fan works?

Where are the fuses mentioned in the manual? If the fans works when I put the + wire that goes the the thermoswitch to the + of the fan, that means the fuses are OK right?

[interfuse]

Where are the fuses mentioned in the manual? If the fans works when I put the + wire that goes the the thermoswitch to the + of the fan, that means the fuses are OK right?

I can't picture what you're talking about, but the fuses are listed on the wiring diagram in the back of the manual.

FYI, my rad fan only kicks in if I'm idling in traffic.

[Squishy]

Where are the fuses mentioned in the manual? If the fans works when I put the + wire that goes the the thermoswitch to the + of the fan, that means the fuses are OK right?

I can't picture what you're talking about, but the fuses are listed on the wiring diagram in the back of the manual.

FYI, my rad fan only kicks in if I'm idling in traffic.

Well .. the thermoswitch has two wires. With thermoswitch I mean the bottom part of the thermostat unit, so not the top one which is the water thermo switch which turns on the TEMP light.

One of the wires that goes into the thermoswitch has 12v on it (plus). The other wire goes from the thermoswitch to the fan.
I attached the 12v wire that goes to the thermoswitch to the wire of the fan, thus skipping the thermoswitch. The fan now works.

Now my question is: Am I correct in  assuming that the thermoswitch is at fault? I don't see what else it can be.

[interfuse]

Now my question is: Am I correct in  assuming that the thermoswitch is at fault? I don't see what else it can be.

Gotcha. My guess would be the switch. You could test it with the switch from your other B4 -- its an easy swap out.

[Squishy]

Now my question is: Am I correct in  assuming that the thermoswitch is at fault? I don't see what else it can be.

Gotcha. My guess would be the switch. You could test it with the switch from your other B4 -- its an easy swap out.

Except I gotta drain the coolant., on both bikes... which I have already done way too many times this winter :(