help with headlight pls

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juntjoo
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help with headlight pls

Postby juntjoo » Thu Mar 15, 2018 3:55 am

I never had high beams because as I recently found the blue wire to the bulb was removed. Incidentally I also found the high beam warning light was out. So put the blue wire back in the bulb, replaced both burnt out bulbs and shortly after blew the headlight fuse. It should seem obvious I think that somewhere along the blue (high beam) wire there is a short but I'm not so experienced with electrical. So I at least took some ohm readings so maybe someone could advise me from here. Below are readings from behind the headlight fuse(that burnt out) all the way to the high beam and warning light and switch.

1) 1.3 ohms across two wires that meet and close the light circuit at the starter circuit open,

2) .6 an ohm from the harnesses between the starter and light switches

3) erratic then floated around 400 ohms from the harness to the switch

4) a bit over 100 ohms from the switch to the low beam

5) 1 ohm from the switch to the high beam

6) 1 ohm from the high beam to the harness

7) .4 an ohm from the bulb and switch harness to the harness before the instrument gauge

8 ) 9 ohms around the high beam warning light at the instrument gauge harness

so if you can tell me which numbers are off then I can try to fix em. thanks
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Folsoml
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Re: help with headlight pls

Postby Folsoml » Thu Mar 15, 2018 5:19 am

Ohms is not what you should be checking for. You should check for continuity with ground.
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juntjoo
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Re: help with headlight pls

Postby juntjoo » Thu Mar 15, 2018 9:53 am

Folsoml wrote:Ohms is not what you should be checking for. You should check for continuity with ground.


got don't check ohms doing that?
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juntjoo
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Re: help with headlight pls

Postby juntjoo » Thu Mar 15, 2018 5:49 pm

oops. i was doing it with the battery connected. i see in videos people disconnect the battery first. so does that mean I'm getting resistance readings of the battery mixed in? I'm still getting the differences essential though between each section of wire tho right? well I know it's the headlight fuse and it looks like it's related to the high beam or high beam indicator light. so unless i find an obvious effect on the wires I'll have to use numbers here right?

so my procedure of going from point to point was useless? my idea was since I knew the headlight fuse went out, I started from there and back tracked through every section of wire. I didn't do each portion to ground, but I closed each section getting readings of exact sections... so come to think of it, battery disconnected or doesn't matter. i isolated each section. If one of those sections was faulty there should be a difference in resistance no? for ex. the low beam wire which worked before when blue high beam wire was disconnected(by op) gave 100 ohms while the blue high beam wire gave 1ohm. shouldn't those numbers closer basically being physically the same, same gauge wire, same direct connection. except the blue branches off headlight in another direction also (to warning light) so while testing blue to switch its connected to circuit to warning light, but from my limited knowledge the current will ignore that path and go straight to switch to the ohmeter I think. okay, I'll keep reading on short circuit testing...
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Folsoml
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Re: help with headlight pls

Postby Folsoml » Thu Mar 15, 2018 6:55 pm

Does your meter have a setting for continuity? Continuity and Ohms are not the same. Presuming that you have a setting for continuity, I would start at the headlight plug. Put one lead on a good solid ground (the green wire connecting to the coils is a good one that's close to the light) and put the other on the end of the blue wire at the plug. Your meter should tell you immediately if you have continuity with ground (not good) or not.

When you say, "since I knew the headlight fuse went out, I started from there and back tracked through every section of wire," What do you mean? Where did you start? At the fuse? And when you "back tracked" were you going back down the harness towards the battery?
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juntjoo
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Re: help with headlight pls

Postby juntjoo » Thu Mar 15, 2018 9:35 pm

Folsoml wrote:Does your meter have a setting for continuity? Continuity and Ohms are not the same. Presuming that you have a setting for continuity, I would start at the headlight plug. Put one lead on a good solid ground (the green wire connecting to the coils is a good one that's close to the light) and put the other on the end of the blue wire at the plug. Your meter should tell you immediately if you have continuity with ground (not good) or not.

When you say, "since I knew the headlight fuse went out, I started from there and back tracked through every section of wire," What do you mean? Where did you start? At the fuse? And when you "back tracked" were you going back down the harness towards the battery?


no, not towards the battery, the other side of the fuse towards everything else. sorry if I don't make sense, I'm still trying to figure this all out.. currently reading up on electrical basics..
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juntjoo
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Re: help with headlight pls

Postby juntjoo » Thu Mar 15, 2018 9:55 pm

as I've read your can do is use a fuse to sacrifice just to note when it goes, which I sure will go when i turn on the high beam. That blue wire goes between the bulb the switch and the high beam warning light. very easy to trace. i should maybe inspect the warning light socket. i never did as it sits deep in this rubber. otherwise rather than going from high beam straight up to the high beam warning bulb it goes into the main harness through whatever it goes towards the battery then back to the little bus station behind the headlight then to the high beam warning light. So maybe the culprit is back there somewhere.the whole thing is taped up though. what do ya think the chances are it's underneath the the tape in the bundle of wires?
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juntjoo
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Re: help with headlight pls

Postby juntjoo » Thu Mar 15, 2018 10:25 pm

well I just spent a little time holding the high beam circuit closed with the warning light disconnected then connected and the new fuse hasn't blown yet. would this suggest it will take a bit more time or voltage as when riding the bike?
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juntjoo
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Re: help with headlight pls

Postby juntjoo » Thu Mar 15, 2018 10:48 pm

according to my meter's manual, less than 120 ohms it will beep. So I would check this from each component to begin ground with the switch closed and it should beep if the the resistance is under 120 ohms? this doesn't seem conclusive. what if my circuit is made to be lower than 120 ohms and this just makes false alarms? well I'll go for it either way then report back...

which reminds me, I was wondering if I needed a "test light" i keep reading about and this continuity test is the same thing!
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juntjoo
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Re: help with headlight pls

Postby juntjoo » Fri Mar 16, 2018 7:15 am

okay, with new fuse ive been riding with low and high beams all morning. actually, my highs for some reason seem to shine a halo in front of me rather than a spotlight. are both filaments in the bulb supposed to shine for high beams or just the one? well I'll keep riding and see that headlight fuse goes out again. hopefully not...
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Folsoml
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Re: help with headlight pls

Postby Folsoml » Fri Mar 16, 2018 7:34 am

juntjoo wrote:according to my meter's manual, less than 120 ohms it will beep. So I would check this from each component to begin ground with the switch closed and it should beep if the the resistance is under 120 ohms? this doesn't seem conclusive. what if my circuit is made to be lower than 120 ohms and this just makes false alarms? well I'll go for it either way then report back...

which reminds me, I was wondering if I needed a "test light" i keep reading about and this continuity test is the same thing!


Do you have this setting on your meter?
Image

A normal circuit should be as close to NO ohms as possible. If you set your meter to the symbol above, it will either beep for a complete circuit or not beep it is not a complete circuit. If you have a wire that goes into the heavily insulated/taped area of the harness, and you want to know if there is a break in the wire somewhere, put one meter lead on one and of the wire and one on the other. If it beeps, there is no break. If you want to know if it is grounded, put a lead on either end of the wire, and the other on a good ground. If it beeps, it is grounded.

A test light is handy, but it will only tell you if a wire is hot or not.
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