Cooling Fan Short to Ground

Over the last few weeks I finally accomplished a few things and fixed some nagging problems: new wheels & tires as well as fix the flickering low fuel light. After I put the fuel pump back in I hooked up the tablet through Buell tooth and checked my error messages. The only one that was showing was the Cooling Fan 1 short to ground. The fan that was in there was a SPAL replacement that I put in about 3 years & 5,000 miles ago. It spun smooth, but wouldn't spin when I tried to force it on through ECM Droid. I checked all of the wires for a short, wiggled everything I could find and disconnected the old fan...still got the same error. I went ahead and ordered a new fan from amazon and swapped out the motor & fan blade. As soon as I did that I was able to clear the error & force the fan to run. I did go ahead and power the old fan with 12 volts from the battery. It fired right up and ran smooth.
It seems strange that I was getting a "short to ground" error when I could find not shorts & a new fan motor made it all go away.

Back to the fuel pump; there was a disturbing amount of crud laying the pockets of the aluminum fuel pump base. The stuff on the blue towel all came out of there.


I fixed the sensor issue by splitting a piece of fuel line and making a sleeve to go between the wires and the aluminum extrusion.


Back on the road again.

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As soon as I did that I was able to clear the error & force the fan to run. I did go ahead and power the old fan with 12 volts from the battery. It fired right up and ran smooth.
It seems strange that I was getting a "short to ground" error when I could find not shorts & a new fan motor made it all go away.

Nicely done on the pump harness. That tiny section of wiring rubbing against the pump housing which is grounded has been a source of blown 10A pump fuses for 20 years now.

This nagging and common FC #36 or "fan short to ground" is because an XB cooling fan has a rather unique relationship with the ECM if you consider how it functions. The ECM not only conducts the ground to activate but also varies the run-speed according to mapped parameters. The moment the ECM sees a resistance value or slightly out-of-wack voltage draw that it doesn't like....here comes FC #36. That is precisely what you experienced.

I'm probably fortunate that the low fuel glitch showed up because there was the same tiny bare spot in one of the fuel pump wires as well. It was only a matter of time before the blown fuses started.



You've got to really zoom in to see the tiny bare spots on the 2 wires.

Win for Boat Ski!!!!