Electrical problem - lighting, horn, etc.

[justintime]

On my '15 FJ-09 all components powered through the 7.5A signalling system fuse stopped working.  This includes headlight eyebrow running light (main headlight is ok), horn, front running lights, rear running light, brake light, and license plate light.  The fuse blows instanty when the ignition is switched on.  I've disconnected each of the above items and the fuse still blows, so neither of these would seem to be the culprit.  I've looked at the wiring diagram and done what I could to follow the circuitry.  Not being a pro, I'm sure I missed something.  The turn signals work as they are supplied voltage via the 10A running light fuse. Just wondering if anyone else has a thought on this problem. 

[skipperT]

Justintime- what mods have you done to the bike that are electrical in nature? Or what has someone else done?
 
Skip

[justintime]

Skip:
 
The previous owner replaced the turn signals with OEM Yamaha LED turn signals, added LED driving lights mounted to the lower fork legs, ECU re-flash by VcycleNUT, replaced OEM horn with louder FIAMM horn, and added OEM Yamaha heated grips.
 
Given the low miles on the bike (approx. 4,000), I have to beleive the electrical problem is most likely associated with the add-ons and not the original electrical system. As mentioned in my original post, power to the turn signals, horn, rear light assembly, and driving lights was disconnected. Fuse still blows when the ignition is switched on. The heated grips are not on the circuit controlled by the 7.5A signalling system fuse. Any suggestions would be appreciated.

[skinkypants]

At the risk of stating the obvious, it sounds like you have a short.
 
To isolate the problem, you might try checking for continuity with a multimeter between the hot side of the component connectors and some ground point. If you see continuity then the fault is somewhere else in the circuit. Keep pulling stuff off until the problem goes away, and your culprit is the last piece you took off.

[justintime]

I reached the same obvious conclusion and did as you mentioned - removed each of the components on the 7.5A circuit and the fuse still blows. So, there must be something else on that circuit that I'm not seeing. Will continue to search this out.

[wessie]

I bet somewhere along all of the mods that someone has trapped a wire and it is now shorting to the frame. I would check the non-Yamaha items first.
 
 
 
 

[skipperT]

I agree.
 
And instead of continuing to blow fuses - use an old turn signal or rig a lightbulb and install it in place of the fuse. The light will stay illuminated (because of the short). Disconnect everything you can think of in the circuit, or pull all the accessories in question. When the light goes off - whatever you just disconnected is where you need to concentrate your troubleshooting.
 
That's one of the easiest ways I know to find a short.
 
Good luck, keep us posted.
Skip

[justintime]

Well, I got tired of digging around looking for funky connections. Took the bike to the local dealer and they found the offending shorted connection. Also, they cleaned up some of the other wiring associated with the accessories which were added by the PO. Been riding for a couple of weeks and everything seems fine. I gave it a good try.
 
I can at least feel good about finding and correcting the previous electrical problem where the replacement Yamaha LED turn signals wouldn't work. That was a short between the hot lead and ground lead for one of the rear signals. The short was not only blowing the fuse, it also fried the signal lamp and flasher. I discoverd that short after unwrapping a ton of electrical tape and examining connections carefully. Had to source the replacement LED signal from Canada, as they are not avalable in the US. Guess I'm batting .500 on electrical troubleshooting.