Headlight Wiring


CB750 New member
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Hi All,

Thanks for having me.

I've got a specific question that I hope you all can answer.

TLDR - low beam not working, high beam is fine. Bulb was checked/replaced. Low/High beam switcher was checked. I suspect it's the wiring as this was done by previous owner and has several additions that are not in use. See questions down below.

My CB750A has an aftermarket (not Vetter) fairing that the previous owner [had] wired. Currently, when connected it will disrupt the battery charging to the point that if left alone will eventually drain the battery (even while in operation). However, if unplugged, there is no issue. What I've learned so far: [1] controls both turns signals together, [2] no effect/ground, [3] main power to headlight, [4] right turn signal + alert sound, [5] unknown/no effect, [6] left turn signal + alert sound. I'm looking to remove all the extras and rewire it, however, there are 2 points that I'm confused about.

Point 1, in the pigtail image connection [2] and connection [5] are unknown. However, I suspect that [2] is the ground. [5] is just a loose dangling wire (could be culprit). WhatsApp Image 2022-04-15 at 5.12.56 PM.jpeg

Point 2, in the headlight image the connector shows [1] ground, [2] drive, [3] pass. However, the [1] ground is not used for grounding but in actuality [2] drive is being used for ground (and/or the unknown). WhatsApp Image 2022-04-15 at 5.43.57 PM.jpeg

Question 1, does the order (ground, drive, pass) matter (i.e., the ground side must be used for grounding) or are they interchangeable as long as each does only one function?
Question 2, does anyone know what [5] is supposed to do or is [5] supposed to be spliced into [3] to make the low beam work?


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