Cooling fan won't turn on

Charlesbusa

Used to be a SoCal Busa
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I got back from a ride and watched my temp go into the red. I checked and know that the fan wasn't coming on.

My first guess is the thermo-switch that turns the fan on went bad. Un fortunately, I need a multi-meter which I don't have to test it,

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My question is how to do these inspections.

For the relay, if I connect Term C to the + battery post and Term D to the - battery post should the fan come on??  What do they mean by checking the continuity between Terms A & B??

For the motor, I don't have an Ammeter.  But if I connect the positive lead to the + battery post and the negative lead to the - battery post, the fan should come on right??   Or would I blow it up??

Any help would be appreciated  
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Hey bud...just got home and I'm tired. Get a hold of me tomorrow and we'll figure it out
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If you can get to the relay just jumper it out with anything, screwdriver, car keys, etc. The fan should come on. You can also turn the fan by hand to make sure nothing has it in bind or the bearings haven't gone out in it. I don't think shorting the sensor will work, it might.
 
plug the fan directly to the battery using standard wires and test the fan out that way..if it works then you prob have my problem which is a bad relay
 
(dadofthree @ Jun. 03 2007,12:58) If you can get to the relay just jumper it out with anything, screwdriver, car keys, etc. The fan should come on. You can also turn the fan by hand to make sure nothing has it in bind or the bearings haven't gone out in it. I don't think shorting the sensor will work, it might.
Which pins do I jump on the relay?
 
Unplug the thermo switch connector from the radiator.
Using a paper clip, screwdriver, or needlenose, jumper the two conductors together.'
Turn on your ignition and if the relay and fan are good - the fan should turn on.
 
(omslaw @ Jun. 05 2007,14:56) Unplug the thermo switch connector from the radiator.
Using a paper clip, screwdriver, or needlenose,  jumper the two conductors together.'
Turn on your ignition and if the relay and fan are good - the fan should turn on.
Cool
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That makes sense to me
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(Devil Dog @ Jun. 05 2007,14:46) forget the fan....ride the 7 fitty!
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Da 7fitty has got the sticky tires on it
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I'm trying to save those tires for trackdays. The busa gets the canyon duty
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Fixed!
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 For now...

So I go outside and use a paper clip to jump the plug to the thermo-switch like Omslaw suggested, and I hear a click.  So the relay and the thermo-switch are working.  So I pull the plug to the fan and it has a blue and a black wire.   hmmmmm

So I call Rich(BA BUSA), as I'm loading the service manual.  Service manual doesn't tell me which wire is ground or positive.   Rich figures if I hook it up backwards it'll only spin the fan backwards, but we decide to try a 12v light tester and see if the fan is getting power.  So I go outside, get a 12v light tester and try to test the leads in the plug to the fan.  Nothing, no juice.  Then Rich suggests checking the fuse and I'm doubtful because the bike only has 6 fuses.  Surely the fan doesn't have its own fuse, guess what it does!  And its blown.

Replace fuse with spare.
Jump the plug at the thermo-switch and viola, fan comes right on.

I feel like a retard...   Always check the fuse first right....

Don't know why the fuse blew, but I drained what was left of the coolant(about 1/2 of what its supposed to have), flushed it, and refilled it.

Then ran the bike for about 25mins as I put everything back together.  Fan kicked on more than 10 times and it worked normally.  Guess the fuse just got too old...

Thanks everyone for the help and especially Rich  
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Glad you got her working, bro! Those things can be real frustrating when you have them, but even more frustrating when it was something simple that fixed it. I do that a lot, so feeling dumb is like everyday life to me!
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