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Discussion Starter #1
Hey Kawa Riders!!!! Please Help! :eek::eek::eek::eek:

I just got my quad back from the shop, I had the bearings in the rear done. While it was at the shop I did the normal maintenance such as oil change, filter, and some New pads in the front. (None of this has anything to do with my issue but just some background)

After I got the quad back everything seemed great for about 2 days of riding. This pasted weekend, towards the end of my ride I noticed the left indicator light came on.

So I did some research on what this light means, since I bought the quad USED I do not have a Manual.
From what I found this light is telling me the quad is OVERHEATING.


After I realized something was going on, I stopped riding and let it cool down. I started it again and found out that my FAN is not engaging.
Up until this point the FAN worked flawless, it was always on when it needed to be cooled and would shut off when everything was back to Normal TEMP.


*********So if someone could HELP me out with trouble shooting this issue would be greatly appreciated.


I'm looking for the most common cause of OVERHEATING, is it the fan itself, or is there a sensor or switch that relays to the fan, and could that be fried?? any other parts involved?

*******************************
***************
*********What steps would you take, or check first?



Is this a Common issue, has anyone else had there quads fan stop working suddenly??


THANKS
for
all
your
HELP!
 

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i would start by checking the fan fuse. its in one of the orange boxes under the hood. There is also a relay under the hood for it as well. should be able to find the part number by searching.

lastly it could be a bad water temp sensor. the sensor is located on the back of the head. if you unplug the connector and the fan comes on either the sensor is bad or the wiring has an issue
 

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Mine has recently done the same thing. The fan, fuse, relay, and temp sensor were all fine. Now it won't start so replacing the cdi box but hasn't came in yet.
 

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Mine has recently done the same thing. The fan, fuse, relay, and temp sensor were all fine. Now it won't start so replacing the cdi box but hasn't came in yet.
Did you test the fan (itself)..?

By running 12v jumper wires from the battery to the fan directly to see if the fan motor is working properly...!
 

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Mine has recently done the same thing. The fan, fuse, relay, and temp sensor were all fine. Now it won't start so replacing the cdi box but hasn't came in yet.
Did you test the fan (itself)..?

By running 12v jumper wires from the battery to the fan directly to see if the fan motor is working properly...!

Yeah and everything checks out perfectly fine
 

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I often forget the safe mode test for this which works for all with stock ECU's.

You can unhook the coolant temp sensor connector and turn the key on. The fan should run.

That is a test that should be performed up front. If it runs but doesn't trip on to cool the bike under use the sensor should be replaced.

If it does not run, then leave the sensor unhooked. From this point you would eliminate the fan fuse, fan relay and fan itself as the next 3 steps before going more in depth to determine if it is a wiring issue or an ECU failure.... which is not all that hard to test for either.

The fuse is easy... swap it. There is a spare in the holder. The relay is easy, swap it with one of the others... all 4 are the same relay and the fan relay is the one with blue wires.

The fan itself, you can take the relay off the plug and jumper the blue/white to blue with 2 straightened paper clips and an alligator clip wire.

If it runs then... well that leaves the pink wire and the ECU itself. Check for continuity beep between the terminal for pink and the frame. If it does not beep, unhook the ECU and check from terminal to terminal. If it beeps also check resistance in ohms. If it beeps and resistance is low to none suspect the ECU. If there is no beep or high resistance suspect the pink wire is damaged.

The pink wire is the control wire from the ECU... basically the ECU reads the signal from the coolant sensor and supplies ground to the relay via the pink wire. The stock ECU makes the testing easy since it cuts the fan on by default as a safe mode if there is no signal from the coolant sensor at all.
 

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Discussion Starter #7
I often forget the safe mode test for this which works for all with stock ECU's.

You can unhook the coolant temp sensor connector and turn the key on. The fan should run.

That is a test that should be performed up front. If it runs but doesn't trip on to cool the bike under use the sensor should be replaced.

If it does not run, then leave the sensor unhooked. From this point you would eliminate the fan fuse, fan relay and fan itself as the next 3 steps before going more in depth to determine if it is a wiring issue or an ECU failure.... which is not all that hard to test for either.

The fuse is easy... swap it. There is a spare in the holder. The relay is easy, swap it with one of the others... all 4 are the same relay and the fan relay is the one with blue wires.

The fan itself, you can take the relay off the plug and jumper the blue/white to blue with 2 straightened paper clips and an alligator clip wire.

If it runs then... well that leaves the pink wire and the ECU itself. Check for continuity beep between the terminal for pink and the frame. If it does not beep, unhook the ECU and check from terminal to terminal. If it beeps also check resistance in ohms. If it beeps and resistance is low to none suspect the ECU. If there is no beep or high resistance suspect the pink wire is damaged.

The pink wire is the control wire from the ECU... basically the ECU reads the signal from the coolant sensor and supplies ground to the relay via the pink wire. The stock ECU makes the testing easy since it cuts the fan on by default as a safe mode if there is no signal from the coolant sensor at all.


Thanks everyone for all the responses, its probably more common now that we are getting into the hotter seasons.

Im going to start working on it this weekend.

From the responses im getting that I should definitely check the fan to make sure its working, that seems to be the easiest starting point.

and thanks for the detailed instructions that's exactly what I was looking for.

Ill update what I find out!
 
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