XS850 power always on


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If my battery is hooked up, I can crank the starter on my bike, whether the key is on, off, and even with the ignition unhooked. Not sure what would be causing the issue here - any ideas?
OK, I'll play.....could be a hidden toggle. I reckon if you leave the battery hooked-up, it will drain it sitting around (wonder it don't burn-up a coil too).

Anyway, battery power is fed through the main 20A fuse on a red wire (~14AWG) spliced into the battery positive cable, exits the fuse box also on red wire that goes to the key switch, then exits the key switch on a brown wire that goes back to the fuse box and feeds the remaining circuits. So, if you have power always, the key switch has failed in an unusual way or someone has (somewhere) jumped the red wire to the brown wire.(guess #1)

Such things can be tested for with a multimeter
Found some interesting items.


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It looks like the red wire from the battery cable is now going to a 10A fuse, and the red/yellow has been swapped to an inline aftermarket fuse. What is that wire for? It looks like it comes off the solenoid down by the positive battery cable.
The solid red has been moved from the original "Main" fuse box space over to where the red/yellow headlight circuit fuse was , but it should still be on a 20A fuse. The R/Y headlight circuit now has the inline fuse. The solid red should start at battery positive cable - could be at the battery or at the battery side of the solenoid. Perhaps the "always on" jumper from red to brown occurs in the headlight bucket at the block connector for the key switch:shrug:
Looks like the harness has been at least partially rebuilt from near the ignition unit up to the fuse box. I will pull that out and see if I find anything weird. Everything in the headlight bucket seems to look normal. Thank you for the help so far!
Well this looks like fun. Also pic of inside of headlight - a few wires that are not hooked up, but they do not look like an issue.


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That brown wire splice in the first pic is actually standard fare on a factory harness and not normally an issue. So to track the "always on" issue probably the next step is to check the function of the key switch - to ensure it hasn't failed weirdly: you should have no continuity between red and brown at the switch's block connector (unplugged) in the OFF position and continuity there when ON.
OK, so, switch unplugged, batter not hooked up, I have continuity at the plug on the harness. Also found another interesting splice. And a pick of the plug, which looks a tad broken to me.


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First pic is normal Yamaha factory fare; the brown from key switch returns toward fuse box and splices into R/W (ign), R/Y(headlight) and Brown (signal,etc) just ahead of entering the fusebox.

The second pic, however could be the source of "always on" if it allows red (power in) to contact brown (power out)
So I tore out the odd chunk of plastic in between red and brown and now everything works as it should. Not sure why that melted plastic would be completing a circuit, but it is working as intended now. Thank you guys so much!


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Awesome, thanks! I guess next is an upgraded fuse block, and or get some actual connectors to replace all that elec tape. I'll take some nice pics tomorrow, it's an insanely nice bike, I'm very excited!