Radiator fan works only with 12v applied

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Boston

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So, My new to me 05 fjr t failed the first stress test.

After doing the valve check and putting it all back together. It overheated. (why wont the fan work)

Applied 12v direct to the fan and it worked.

Did the self test 51 and the relay puts 12v to the connector. (will not spin the fan)

Ohm out the fan at the connector and nothing.

When the fan is check with meter for open or closed circuit it is a closed circuit. (like checking a wire for a break) beep.

Have you seen the price Mother Yamaha wants for a fan. ouch.

Placed a order for a preowned fan.

John

 

dcarver

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Wait. The fan rotates when 12 vdc applied directly to fan terminals? Then the fan is good.

Did the self test 51 and the relay puts 12v to the connector. (will not spin the fan)
Me thinks the relay can provide voltage but insufficient current. I'd try a new relay first...

 

RossKean

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Doesn't make sense. What is the difference with 12V being applied directly or via the relay? (Maybe I am missing something?)

Did you actually check for 12V at the connector to the fan with the self-test? If not, it seems to me that there may be a problem with the relay or a broken wire between the relay and fan. IIRC, the relay for the headlight is the same as the fan relay??? If so, you can swap them to test the relay. Could also be that the relay contact is pretty burnt and although it might deliver 12 V (unloaded), it might have a large voltage drop under the load of the fan and unable to run it.

Edit: Carver gave somewhat the same answer in a lot fewer words!

 
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Boston

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I did check during the check 51. put the meter on the connection coming from the relay to the fan. Had the fan disconnected.

I'm getting 12v to the connector with test 51.

I'm going to test with a 12v motor and see if it will run.

John

 

RossKean

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After your valve check, is the temperature sensor correctly placed and is the radiator full (not air-locked)? This is a fairly common issue if you are not careful. Doesn't explain the failure of the diagnostic to run the fan...

 
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Boston

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I did a good job at filling the coolent. I used water (not tap water) And when it hurled all over my floor from overheating I was glad it was just water.

I ran the motor 3 times before the stress test. Overflow was spot on the last time.

Temp sensor is proving to be ok..

 

Boston

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Just swapped the relays and no change.

Bypassed the blue wire (with a jumper) Then did test 51. And no change.

 

hppants

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I'm trying to think of what could cause this in association with the valve check, and I'm drawing blank. So, how about some crazy out of the box ideas?

1. Kinked coolant hose where the metal coolant pipe connects to the coolant hose?

2. Stuck thermostat?

3. Re-seat the temperature sensor wire connection?

4. The temperature sensor got cracked/damaged during the valve check?

5. You put a piece of rag or paper towel in the cylinder head holes where the cooling pipe goes to keep shims and other stuff from falling in there (I do that), and forgot to remove it when you installed your cooling pipe?

Of course, none of this is logical because in any case, if the feedback from the sensor (correct or otherwise) is telling the ECU that the motor is overheating (and it is), then the fans should start automatically.

5.

 

harper

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This sounds a lot like there is a high resistance path to or from the fan. Like a corroded connection at the fuse or relay or a corroded spider in the ground path.

 

Boston

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Ding Dind Ding We Have A Winner. harper. Johnny tell him what he WON !!!!!!! :)

A corroded connection at the plug under the tank. The same one that everybody is finding very corroded pins.

It will carry 12v but no amps.

pics to follow.

For sale: one used fan for a 05. i bought a spare just in case. ( i think my fan is good)

 

harper

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Ding Dind Ding We Have A Winner. harper. Johnny tell him what he WON !!!!!!!
smile.png

A corroded connection at the plug under the tank. The same one that everybody is finding very corroded pins.

It will carry 12v but no amps.
This doesn't seem like much of a prize to me. What will I do with a corroded connector? I guess I could put it next to my corroded ABS sensor wells.

 

BigOgre

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Ding Dind Ding We Have A Winner. harper. Johnny tell him what he WON !!!!!!!
smile.png

A corroded connection at the plug under the tank. The same one that everybody is finding very corroded pins.

It will carry 12v but no amps.

pics to follow.
Yeah, you ain't the first. From my '04:

IMG_20151014_125448261_HDR.jpg


Glad you got it sorted out.

 

WBill

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My '05, with 78K miles, just had almost exactly the same situation: recent valve check, overheated in traffic because radiator fan didn't engage. My shop just called me with the diagnosis this morning. There was rock stuck in the fan.

I live about half a mile down a cinder road, so I guess that's how I picked it up. It wasn't visible through the fairing, so I guess you had to take the plastic apart. Chalk it up to amateur motorcycle mechanic school tuition.

WBill

 

Boston

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To get the pin out of the connector was a PITA. (no extra wiring room) I just happen to have some pins in the box.

Fan cycles as it should. Now if I could only find a local store that sell 5/16 vacuum hose spring clips. For the vacuum connection at the TB.

To post pics is a learning curve thing. and ,well. Same connection that BigOgre posted a pic of.

I can send pics to email.

Big thanks to the collective.

 

RossKean

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Are you talking about clips for the rubber caps for the TB synch ports? They are under (slight) vacuum (no pressure) and the caps are pretty snug. Lots of people don't bother replacing one of the springs if lost (and lots of them get lost!).

 
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Boston

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Ding Dind Ding We Have A Winner. harper. Johnny tell him what he WON !!!!!!!
smile.png

A corroded connection at the plug under the tank. The same one that everybody is finding very corroded pins.

It will carry 12v but no amps.

pics to follow.

For sale: one used fan for a 05. i bought a spare just in case. ( i think my fan is good)

https://www.use.com/4c5ce4c53da6732402fc?p=1

 

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