Author Topic: Headlight only functional in neutral and when clutch is engaged.  (Read 857 times)

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Offline Kreb

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Hey guys,

I just wired up a new headlight on my 76' Cb 550. It looks great but its only lighting up when the bike is in neutral or when the clutch is engaged. I must have wired something up wrong but i'm not sure what it could be. For the headlight I wired in the new socket exactly how the older one was so it is most likely something else thats wrong. Let me know if you have any ideas.

Thanks

Offline calj737

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Re: Headlight only functional in neutral and when clutch is engaged.
« Reply #1 on: June 20, 2019, 08:33:38 pm »
Are you using an m-unit? If so, it’s pretty darn easy to wire it correctly. Pretty hard to wire it wrong.
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Offline HondaMan

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Re: Headlight only functional in neutral and when clutch is engaged.
« Reply #2 on: July 05, 2019, 07:15:48 pm »
If stock: the Green-Red wire in the headlight is the Neutral-safety circuit. The headlight is likely using that for its ground, so use a different Green (only) wire for the headlight.
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

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Offline ofreen

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Re: Headlight only functional in neutral and when clutch is engaged.
« Reply #3 on: July 06, 2019, 09:39:16 am »
Yes, the headlight is not grounded correctly.
Greg
'75 CB750F

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