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Are there supposed to be loose wires in the headlight assembly?

gbwithacb

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Hey everyone,

New member, first time post! I looked through the previous posts in this category but none that seem to fit my problem.

I picked up a real dinosaur 1979 CB750. It was stored for a heckin' long time. The previous owner must have prepped it for long term storage. There was no brake fluid, oil, or gas in it. So I'm assuming that all the wiring is intact.

However, once I put a battery in, only the brake light comes on and stays on. The headlight only comes on if I push the key all the way to the right, or if it is between the on and ignition slot. Sometimes it stays on in the ignition slot.

Earlier, the indicators were working briefly (but they weren't blinking). There was also a brief flash of the "oil" light came on, too. But that was for a split second.

I figured I should change the fuses, so I did, but that didn't fix anything, and now the indicators don't work but the brake light still goes on and stays on.

So, I opened up the headlight assembly to have a look. I found three loose wires. A green one, a brown one and a black one. (They aren't loose, they have that plastic tubing around them.) I looked at the wiring diagram (picture attached) and these wires just end. Is that supposed to be the case? I traced the green wire and that seems to be ground.

If anyone has any suggestions on how I can fix this, I'd be really grateful! All I want to do is get this baby running before my holiday ends in two weeks. If I can't, I might just have to sell it for parts ):

wiring.jpg
 
It's also possible that the battery I'm using isn't 100% charged. I don't have a battery charger, I just poured the acid into a battery and let it sit for a few hours.
 
You have to 100% charge a brand new battery. So-called 'dry charged' is the pits and asking for hair pulling problems. And if the person yanked battery acid even to have you using old battery you are wasting your time.

There can be a lead or two unused inside the headlight.
 
1st you need a good battery, minimum of 12.8v charged level. The most common cause of the lights etc doing odd things is bad or no grounding. Current will always take the path of least resistance so if the ground connections are poor, i.e rusty or broken, lights will do the oddest things. Example, I once had a car where headlights came on when the brakes were used! Cause: bad ground on the brake light circuit, the current found a ground through the head light wiring. Get your self a digital multimeter, one with a buzzer, and start checking out the wiring for breaks and continuity.
 
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A battery at only 12 volts even is a dead one.................a brand new battery will read around 12.8 volts or so, and considered good all the way down to 12.3 or so, at least on modern computer controlled cars. These bikes it can drop a bit more but the ignition spark boxes won't like it. That last .2-.3 volt is the killer and many people don't catch that.

When I used to test in parts most cars began to show issues at 12.2 and lower. Electronics are far more b-tchy about having full power than other things. Having enough power to whirl starter without drawing power off ignition becomes an issue. 11.99 volts is a dead battery by all textbooks teaching on the subject.
 
As a mistake putting things back together once I plugged in the ignition harness into a different one, it was doing something similar to me, just as a double check make sure all the harness plugs are in the correct spots
 
A battery at only 12 volts even is a dead one.................a brand new battery will read around 12.8 volts or so, and considered good all the way down to 12.3 or so, at least on modern computer controlled cars. These bikes it can drop a bit more but the ignition spark boxes won't like it. That last .2-.3 volt is the killer and many people don't catch that.

When I used to test in parts most cars began to show issues at 12.2 and lower. Electronics are far more b-tchy about having full power than other things. Having enough power to whirl starter without drawing power off ignition becomes an issue. 11.99 volts is a dead battery by all textbooks teaching on the subject.

It was 1130 at night, had been in the shed all day working on my bike, my excuse anyway!
 
Hey just wanted to let you know that I finally got her running the other day! However, there is a new problem. I'm gonna look around here see if I can find an answer! Thanks for all your help
 
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