radiator fan fuse keeps blowing

I had dropped my bike once and bent the tabs on the radiator coolant temp sensor. This gave me an intermittent short. What I'm getting at is that it's more than likely a wiring issue as opposed to a fan issue. If the fan turns freely I would suspect wiring.

Is there a wattage on the fan?

berger said:

If the fan turns freely I would suspect wiring.

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I agree with berger.

The fuse is just telling you that something is wrong. I use my bike to jum stumps and climb hills all day, the fan will run and run without blowing a fuse. Keep the 5 amp fuse.

Good luck finding the short.

You are very right, but if the fuse is under rated it could blow quite easily. But the fan would have to be over 60 watts and i dont think they are.
Ive got an unfitted fan and the fuse is 5A so ignore the 10A one.
Have a look at the thermo switch, they can sometimes go faulty inside

I measured roughly 2.4Amps 29W for the Fan
09 FE570 What's the wattage output?


It cannot be the Thermo Switch blowing the Fuse. If any of the brown wires on the Thermo Switch shorted together or shorted to Earth or the Temperature Switch was faulty and shorted the only thing that would happen is the Fan would come on.
It cannot be a short on the Blue/Yellow or Blue/Black Wire as the 10Amp fuse #4 under the seat would blow.
It may be a short on the Black Wire between the Fan and Fuse #6, or a short in the Fan if the 5Amp Fuse near the Fan is blowing (Fuse #6)

I am not sure how many Amps the Diode can handle so a 10Amp Fuse in place of the 5Amp Fuse may or may not damage the diode. If you cannot see any shorts in the Black Wire, I am guessing it is your Fan.
Are the Fan Blades getting caught on something bent or broken?

Come to think of it it was the fan harness that got pinched and the thermo switch spayed connectors got bent as well. the pinch spot was not real obvious and the short was intermittent.

fljar said:

First off... HOLY CRAP you guys are helpful. Really, a diagram?!? Just guaranteed a doantion there, many props, thanks. :cheers:

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I can't really speak on behalf of Json who runs this great web site cause I don't know him from a bar of soap, but I am sure he appreciates the donations. Thanks. :cheers:

fljar said:

Is there some sort of "regulator" that could be faulty? I say that because theoretically, when I really rev the bike, maybe that's when it blows???

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Yes there is a Voltage regulator that regulates the voltage produced by the alternator to the Battery. I did some measurements awhile back in this post:
Max system voltage on '09 or later Husaberg??


You can just start the bike and connect a Multimeter across the Battery. Have the Multimeter switched to DC Volts on a range like 20Volts or higher.
You should see this:
Measurements taken with a Fluke Multimeter and giving the ol 570 a good bit of throttle.
14.47 Volts with no accessories turned on.
14.38 Volts with High Beam Switched on.

Just a thought but it would pay to check your Battery terminals are tight, Loose terminals have caused a few issues before on UHE (not blown Fan fuse issues but it is worth a check).

Make sure you post the results of the problem when you eventually find it. We can use that advice for the next person that has the same problem.

berger said:

Come to think of it it was the fan harness that got pinched and the thermo switch spayed connectors got bent as well. the pinch spot was not real obvious and the short was intermittent.

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Come on Berger keep up with the pace mate, it can’t be the spade connectors on the thermo switch. :lol: :lol:

you should run an amerage draw test on the fan just to eliminate that from the equation before trying to find an "intermitant non existent short circuit"...even a 5 dollar volt meter that has an amperage setting can perform this test, connect the meter (while on amperage setting) "inline" with the fan circuit wherever is easiest, probably at the fan, unplug the fan connector and place one lead from the meter to the fan itself and the other lead to the connector side (on the same wire as the first lead ex:red wire at and and red wire on connector) then when the fan runs see what the number of the amperage draw is, davo had 2.4 amps draw, my fans although a totally different style of fan setup also draws 2.4 amps, if yours is reading 4.8 amps or something high then either your circuit has high resistence or more likely the fan is just worn out or slightly seized internally and casuing the excess power draw (which you could then perform an ohm test of the wiring of the circuit to make sure there isnt a connection issue or corrosion issue thats causing the excessive power draw) its very common in the automotive feild for fans to get some water intrusion or whatever and the fan to still work and sound normal and blow fan fuses, also once the fan is hot the amperage draw can change
i personally would get two long jumper wires, connect one to the batt- the other to battery + and then through the meter on one of those and to the fan and the other right to the fan and watch the meter and then just let it run for 15 minutes or something to see how the draw changes, you dont need to overheat the engine to make you fan runs, you already know it all works

davo is like a service manual on two wheels! i love all the illistrations!

fljar said:

So Davo - just looked at the manual and the US models do not have the #4 fuse under the seat for the fan (the #4 is not used in US models according to the manual). I mention this just to see if that changes your theory as I have not yet had a chance to go on an extended ride to test (put the bike up on a stand though and left it running; the fan turns on and off like it's supposed to).

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Hmmm, I don't understand as the Workshop manual shows the same Fan wiring for EU, AUS and USA. According to the Workshop Manual, they all use Fuse 4 :scratch:

Bergini said:

davo is like a service manual on two wheels! i love all the illistrations!

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Thanks Bergini :-D Wish I could ride as good as I illustrate :roll:

Davo said:

It cannot be the Thermo Switch blowing the Fuse. If any of the brown wires on the Thermo Switch shorted together or shorted to Earth or the Temperature Switch was faulty and shorted the only thing that would happen is the Fan would come on.

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Not exactly - if the hot wire shorted to ground, it would blow the fuse. Otherwise, yes, if the switch "shorted", it would just turn the fan on.

I thought that, but both the wires on the thermo switch are ground, so the fan would just come on.

I didnt realise it was switched earth, cos im a silly billy

OldNewbie said:

Davo said:

It cannot be the Thermo Switch blowing the Fuse. If any of the brown wires on the Thermo Switch shorted together or shorted to Earth or the Temperature Switch was faulty and shorted the only thing that would happen is the Fan would come on.

Click to expand...

Not exactly - if the hot wire shorted to ground, it would blow the fuse. Otherwise, yes, if the switch "shorted", it would just turn the fan on.

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OldNewbie, you would be correct if there was a 12V positive wire ("hot wire") connected to the Thermo Switch, but there is not. There are 2 wires connected to the Thermo Switch:
1. An Earth wire that would do nothing if shorted to Earth cause it already is Earth :wink:
2. A negative wire from the Fan that is looking for an Earth to complete the circuit and spin the Fan. So if that one shorts to Earth the Fan spins (assuming the engine is running and the Power Relay is on) :wink:

Davo.

in the circtuit shown in the picture the only wires that would blow the fuse if shorted to ground would be blue/yellow, blue/black, and black, internal fan short would cause change of speed/excessive amp draw or not work, short in wiring on ground side between start of fan and the start of earth coming into thermo switch and including inside thermo switch would cause fan to run all the time, short to ground after thermo switch to ground side source would cause nothing noticable... a properly engineered circuit will always have the switch on the ground side so that the switch will last, when the power side is switched there is a larger spark that results in premature switch failure

Hey guys, I have a similar problem. My fan that was installed at the dealer has never worked at all. I shorted the terminals at the temp sensor and no fan comes on at all. So we pulled the tank, checked the wiring everything looks ok but there seems to be a couple of people that have said that there are multiple connections that the fan can plug to? Maybe 2? The one I am plugged into now from the stock husaberg fan when checked with a voltage meter says I have a ground missing? Hungh? WTF!? We checked all the way back to the battery and all the fuses in the fan and at the battery, nothing popped or missing.

Suggestions?

Thanks for the help

if you have power and no ground then you have to follow the ground wire back to its source, there is no fuse on the ground side, if a fuse was open you would not have power either. i assume you should have ground at all times, if you dont with at least key on would indicate an open ci rcuit in the wiring, ei: pushed out terminal in connector, wiring damage, or incorrect wiring if there is really a different connector somwhere that is supplying ground.
verify a connector in the ground circuit wasnt damaged during install, make sure there isnt another connector to plug into it. then would either have to trace back the wiring to see if the harness ever goes to ground and fix the problem as necessary or supply it with a ground of its own from a common frame ground or the battery to make it a different circuit thats basically the same as the diagram shown.
maybe someone else will chime in and tell you where ground starts the circuit or if there is multiple connectors, either of which would make your life easier, you may get better results if you started a new topic as you problem is not the same as the original one that started this topic...

I picked up on something that you guys may or may not know already. The end of line diode that pushes in on the harness and completes the ground. I'm told you can jump this and it will work without but I also read that it might cause issues if you did higher speeds and it "windmilled" causing current to go back through the system.

Dunno yet but but mine wouldnt work if I bridged the 2 thermostat terminals previously. Found the diode missing and well see what happens.

I'll keep you all posted.