Tail light circuit - Page 2 - Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums
Where does this wire go?
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post #11 of 13 (permalink) Old 06-09-2019, 02:05 PM
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I would check the ignition switch "puck". Based on symptoms and your location i would suspect water in the puck has caused corrosion, open it up and look for the damp green mess of verdigris caused by corroding copper. That's usually what I found caused most electrical problems when I lived in blighty, Same goes for the JB, the circuit card is not coated so will corrode readily and the connectors are unplated copper so will do the same. Clean all the crap out and a shot of WD-40 to dry it up should fix it

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post #12 of 13 (permalink) Old 06-09-2019, 09:23 PM
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Sounds like you're so far in the weeds that the schematics in the manual aren't going to be of much use.
For curiosity's sake, when you compare your 8-wire plug at the junction box with the schematics, what wires are attached at pins 7 and pin 17? From your ignition/tail light behavior, it sounds like the PO moved all the dash/tail light circuitry on the red/blue wire from pin 7 to 17 to isolate that circuit from the headlight.

The ignition puck is most likely fine, since the circuit still passes through the puck without a vampiric draw when the tail light fuse is removed.

I'd unplug the tail light and the 8-wire JB connector, then check the ohms between the tail light wire (red/blue now on pin 17???) and ground, and as a sanity check also measure the the tail light constant voltage leg to ground. You'll likely find there's a path for current, and that will at least limit what wires to look at. Follow the speedometer light wire backwards as far as you can (he had to have chopped the harness somewhere) and check the splice. Same for the tail light. I'm guessing he kept the factory tail light connector on the bike and spliced the new hardware in further to the rear?

1992 US-nonCA * tuxedo mod * r/r relocated

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Wiring Diagram + annotations * still undergoing revisions, but still more useful than the generic one. Let me know if you find mistakes or think something additional should be added
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post #13 of 13 (permalink) Old 06-10-2019, 04:24 PM Thread Starter
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Frustratingly it's raining heavily...good ol' British summertime! Bikes stored outside so can't fix anything 😠 Cheers though Thorn, I will try everything you've suggested when possible.
I did expose the whole wiring loom a few weeks back to clean and learn about it all and see what was missing [attac2h]46005[/attach] . Everything according to the manual is there, but maybe not quite where it should be. At least now with your help I'm narrowing down what's fuc... Tomfooleried up. (I'd like to point out the issue of colourblindness at this point. Everything takes twice as long!!)

TonyO cheers buddy! Previously had the puck apart when this all started. Cleaned it up and covered in vaseline to protect it from moisture.
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