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Discussion Starter · #1 ·
I was riding the bike all weekend and there were no problems with the lighting. This morning I went to start it and found headlight dark. I thought it was a bad bulb so I swapped it with a good spare, still dark. Checked and replaced head light fuse, still dark. Now I am suspecting a short somewhere. I also noticed that the high beam indicator light is now also lit up. If I leave the bulb unplugged from the harness then the high beam indicator light is not lit up. So I suspect I have a short somewhere. Cycling the high/low switch makes no change to either the headlight or the indicator light.

just looking for pointers about how to troubleshoot and key points to try.

Thanks
 

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The high beam indicator receives power from the Blue wire at the headlight socket, that short pigtail wire. Test using a testlight or VOM utilizing the Green ground wire in the headlight socket
Key ON, headlight switch on LOW. you should have power on the White wire.
Key ON, headlight switch on HI. you should have power on the Blue wire.
If you have no power to either then switch the ground lead to the frame or any solid Green wire in the harness and recheck. You may have lost ground.
 

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Discussion Starter · #3 ·
Thank you very much, I will do it this weekend.
Mike
 

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Discussion Starter · #4 ·
Yes I proved I have lost the ground. I made short sections of wire between the socket and the bulb for each of the white and blue wires and a longer section for the green wire. All works well when I ground the headlight to bike. Now to chase why the headlight ground is poor.
Mike
 

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The solid Green wires in the bucket are all ground wires. Check battery voltage at the battery, then check from positive battery terminal to any ground in the bucket, reading should be the same. There is a ground lug from the harness to the frame at the CDI unit.
 

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Discussion Starter · #6 ·
Thank you. I have both the Clymers manual and the FSM. In the Clymers manual on their version of the wiring diagram, the legend refers to both a "ground" and a "frame ground". What is the difference? The FSM only shows a ground. In the diagram I counted 7 ground symbols. Does that mean there are 7 points somehow connected directly to the steel frame of the bike.?
 

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There is only 1 actual harness ground, by the CDI unit and uses one of those mounting bolts. Other grounding takes place thru the steering head bearings and engine mounting points by physical contact.
I don't trust the one ground wire point so I have a second wire running from there directly to the negative battery cable and another from the upper engine mount as well.
 
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