Error code 36 Fan issue. Short to ground.

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Beebop

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Joined
Dec 28, 2015
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Well it seems that as my mileage climbs, so do my issues.
06 XB9SX 90 000km.
I just replaced the pump assembly last month, and its been running great, but
yesterday the CEL started coming on each time the fan should have engaged.
I have done the following:
Fan was replaced about 6 yrs ago.
Unplugged the fan connector and applied 12V to the fan, it runs, albeit slow.
Ran a fan test using Buelltooth.. fan does not run.
Tested ECU pin 6 using fan test, and it does apply a ground onto the black/orange wire.
Tested the black/orange all the way to the fan connector, and the ground works all the way.
Tested wiring to ground and to positive with both ends disconnected, all tests correct.
Tested 12V and ground during fan test, and all tests correct at the connector.
The fan tests approx 5 Ohms across the motor. Not sure if this is correct.
What I did find strange is that the CEL comes on intermittently even straight after startup
when it is cold. When out on the highway at 120+ kmph, it never comes on.
I'm hesitant to start throwing parts at it without understanding why I get these symptoms.

Would it make sense to extend the wiring and connect my wife's XB's fan and re-run the fan test ?
If it does work, does that indicate that my fan is faulty?
I have done some reading, and it appears that there are cases where a fan "tested" ok, but wasnt.

All ideas/suggestions welcome.
 
yesterday the CEL started coming on each time the fan should have engaged.
I have done the following:
Fan was replaced about 6 yrs ago.
Unplugged the fan connector and applied 12V to the fan, it runs, albeit slow.
Ran a fan test using Buelltooth.. fan does not run.

Sounds like the answer is right there


Would it make sense to extend the wiring and connect my wife's XB's fan and re-run the fan test ?
Why not just run the fan test on your wife's bike to see if her fan performs like yours?


If it does work, does that indicate that my fan is faulty?
I have done some reading, and it appears that there are cases where a fan "tested" ok, but wasnt.

What do you mean by "tested ok"? Not running on the test would indicate it failed the test.
If the fan is struggling to perform as designed, that sounds like a fan that did not test OK and wasn't OK, regardless of the age of the fan. Maybe you can get the manufacturer to warranty the fan, if you feel it failed prematurely.
 
Sounds like the answer is right there



Why not just run the fan test on your wife's bike to see if her fan performs like yours?




What do you mean by "tested ok"? Not running on the test would indicate it failed the test.
If the fan is struggling to perform as designed, that sounds like a fan that did not test OK and wasn't OK, regardless of the age of the fan. Maybe you can get the manufacturer to warranty the fan, if you feel it failed prematurely.

tested ok, as in it works if I power it directly from a battery.
 
tested ok, as in it works if I power it directly from a battery.

There are lots of things in the world that are “working” but not working correctly. If the motor is turning slowly when directly connected to a battery and not at all when connected to the ecm. There is your sign.
 
ok, so today I had an opportunity to do some more in-depth troubleshooting.
Removed the fan completely and wired it directly to the bike battery. It ran flat out as it should.
No oil on the fan or rear cylinder, all nice and dry. Fan turns smoothly with no noise or play
evident in the bearings. Plugged the fan into the wife's bike and it fires up when I connect
pin 6 on the ECU to ground, just as her own fan does (for some reason, the Buelltooth would not
light up on her bike so I could not run the fan test). What sadist designed a fan with a one inch power cord?
At this stage I am happy that the fan is 100%.
I went back to my bike and did some further testing. The ECU grounding on pin 6 is evident all the way
down to the fan. I checked this several times with the fan test and by manually sticking a grounded
pin into the socket. 12V however is not seen at the fan , or connector. I dont know how I missed
that yesterday. Anyway, if I run a positive from the battery to the fan and re-run the test, the fan kicks
in as it should.
So at this stage I'm confident that my problem is a missing 12V at the fan. I did check both sides
of the fan fuse and 12V is there. So next is to delve into the wiring diagram and see where that wire runs
and follow it through. I hate wiring..
 
^^^^^^^^^^^^^^^^^^^^^^

Look for a chafe or break in the wiring loom where it runs over top of the rear cylinder. They are known to chafe in that area and dump assorted fault codes into the ECM including ECM FC #'s 13 for the O2 sensor and #36 for fan voltage. Both will intermittently activate a flashing ECM fault light.
 
^^^^^^^^^^^^^^^^^^^^^^

Look for a chafe or break in the wiring loom where it runs over top of the rear cylinder. They are known to chafe in that area and dump assorted fault codes into the ECM including ECM FC #'s 13 for the O2 sensor and #36 for fan voltage. Both will intermittently activate a flashing ECM fault light.

Thanks Barrett, That will be my next check.
I have had the intermittent "rear O2 sensor inactive" error, but not for quite a while.
At least the problem does not involve trying to get a fan over from the US. Thats
already a plus for me.
 
My pleasure Robin. Simply put, your ECM is seeing repeated resistance values it doesn't like which in turn is initiating all these actions. If you've determined the fan is NOT the culprit, then the problem typically lies in the wiring harness...harness plug connection...or failing ECM.
If it ultimately is a faulty fan, the Spal replacement well documented and easily obtainable thru a multitude of sources online.
 
Happyness is:
So the fan cut off its own supply.
Break was right where the loom passes through the fan shrowd.
Took all of 10 min to find and 20 min later she was fixed...
IMG_20240126_172022.jpg
IMG_20240126_172027.jpg
 
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