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Discussion Starter #1 (Edited)
So I’ve been working on restoring this bike for a couple years and I’m in the midst of figuring out the wiring right now.

Since I bought the bike (and it ran) it has been blowing the fuses for the tail/meter. Only thing I can find modified is where there is an add-a-splice on the brown/white meter light wire which goes to nothing, and another add-a-splice on the black wire coming from the regulator under the gauges with a short wiring coming from it but not attached to anything.

Had a friend “helping” and we laid a piece of tinfoil across the fuse slot and found that the brown/white meter light wire gets hot. Only problem is now I keep blowing my main fuse by the battery, which wasn’t a problem before.

So to sum it up, now I keep blowing my main fuse and the tail/meter blown fuse is still an issue.

I do have a multimeter now if it would help me at all. I have minimal experience with wiring but could use some help if anybody knows where to start?
 

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1982 cx500tc turbo
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69 Posts
Well first of the fuse is there to protect
Using tinfoil is not a good thing to do
So now you know where the problem is. Disconnect the wire and see what happens
the wire that got hot is the problem most like
Not the best way to find a short to ground

TLD
 

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Discussion Starter #3
Lol yes I know that, I was getting frustrated, and there may have been alcohol involved. I guess my bigger concern is why is my main fuse blowing now?
 

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1982 cx500tc turbo
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The old liquid for of wisdom LOL
start removing all the fuses
(You might have caused more damage then just the one wire)
Replace the main fuse and see what happens
start to install one fuse at the time
This way it might single out where or what circuit the short is in
Good Luck

TLD
 
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Replace the fuse with a 12 volt light bulb, It can indicate current flow without blowing like a fuse, but still protect the circuits.

Read the wiring diagram like a road map. start at the battery positive and follow a circuit until it comes to a ground, i.e. returns to the negative battery post.
 

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'84 CX650E that is evolving into a GL500
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I recommend starting with all of the fuses removed and connecting the light bulb in place of the main fuse (as Mike said, the bulb will limit the current and give you a visual indication when current flows).
  • When you turn the key on the bulb should glow dimly because the ignition circuit is not protected by a fuse but if you turn the kill switch on the right handlebar Off the bulb shout go out.
  • Put the other fuses back in one at a time.
---The bulb should be fairly bright with the headlight fuse in but should go out if you unplug the headlight.
---The bulb may light dimly when each of the other fuses is in place but will probably be very bright when the fuse for the offending circuit is in place.
- With just the fuse for the offending circuit in place start moving wires around in various parts of the bike while watching the bulb. If my suspicion is correct when you move the right wire and the bulb will go dim and I wouldn't be surprised if it is one of the brown wires in the area of the tail light.
--- When the bulb goes dim examine the wire you just moved for worn or damaged insulation.

Another possibility occurs to me: You didn't happen to replace the bike's keyswitch did you? The keyswitch for CX500s with Capacitor Discharge Ignition is different from the one needed for bikes with Transistorized Ignition like yours; I can never remember whether it is CDI switch in TI bike or the other way around but incorrect keyswitches have been known to blow fuses....
 
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