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Discussion Starter · #1 ·
Just bought the bike a couple weeks ago headlight didn't work for the previous owner either and he didn't bother to mess with it he just replaced the bulb but still nothing. I replaced the mangled original main wiring harness and still nothing for the headlight or tail light no idea what it could be love some feedback! Thanks :)
 

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Just bought the bike a couple weeks ago headlight didn't work for the previous owner either and he didn't bother to mess with it he just replaced the bulb but still nothing. I replaced the mangled original main wiring harness and still nothing for the headlight or tail light no idea what it could be love some feedback! Thanks :)
Check the fuses?
 

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I did check the fuses and they were all good. Would you know about anything else?
Get a test light or multi meter and start testing your headlight circuit for power and ground. Start your test at headlight and follow wires for power and ground until you reach switch(if used) from there proceed to where switch is powered. Eventually you should find where your absence of power has originated. It sounds simple but this is how electrical defects are found. Check fuses and grounds first, check bulbs and check switches and wiring. Replacing wiring harness does not help you if you have no current to send through the wires. Test circuits for current.
 
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Discussion Starter · #5 ·
Get a test light or multi meter and start testing your headlight circuit for power and ground. Start your test at headlight and follow wires for power and ground until you reach switch(if used) from there proceed to where switch is powered. Eventually you should find where your absence of power has originated. It sounds simple but this is how electrical defects are found. Check fuses and grounds first, check bulbs and check switches and wiring. Replacing wiring harness does not help you if you have no current to send through the wires. Test circuits for current.
Okay I will try that next chance I get thank you!
 

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See if you can find factory wiring diagram for your bike if possible. It may help identify your problem circuit connection point for you. This would allow you to check for presence of current or absence of current from both ends of suspect circuit. You may find free download for your bikes factory shop manual online or check our search feature on forum here for a source. I think we have a thread here describing where to get one.
 
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Discussion Starter · #8 ·
I presume all the other lights are working?
Yeah so that’s what’s weird to me my tachometer and everything on it works and back when I had my turn signals hooked up they all worked but just not the main headlight low or high and tail light
 

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Your description just described a faulty ground connection exactly. Check the metal surface where connector terminal contacts frame or wherever ground is connected and clean surfaces to shiny metal and put dielectric grease or any grease on shiny parts to retard corrosion. Check the ring connectors carefully on ground wires. Some mechanics are careless when installing grounds and tighten with power tool and rotate the connector until it stresses the wire and breaks off strands of wire inside the crimped connector. You may see the wire appears sound but may only have a few strands remaining and cannot supply enough current for all circuits to function. Always apply artifical ground with separate jumper wire directly to battery terminal to ensure your ground circuit has not failed. Indications of faulty ground are dim bulbs or switching one function on and it works correctly until a second or third function is switched on. If there is any doubt ground ring connector is bad, simply cut off connector and replace it.
 

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Discussion Starter · #10 ·
Your description just described a faulty ground connection exactly. Check the metal surface where connector terminal contacts frame or wherever ground is connected and clean surfaces to shiny metal and put dielectric grease or any grease on shiny parts to retard corrosion. Check the ring connectors carefully on ground wires. Some mechanics are careless when installing grounds and tighten with power tool and rotate the connector until it stresses the wire and breaks off strands of wire inside the crimped connector. You may see the wire appears sound but may only have a few strands remaining and cannot supply enough current for all circuits to function. Always apply artifical ground with separate jumper wire directly to battery terminal to ensure your ground circuit has not failed. Indications of faulty ground are dim bulbs or switching one function on and it works correctly until a second or third function is switched on. If there is any doubt ground ring connector is bad, simply cut off connector and replace it.
Right on thank you so much that would make sense because the people before me both tampered with the wiring and I did see an extra ground that I put on so I don’t know if that is actually a normal thing or needed but I’ll test it out thanks so much!
 
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