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strange problem just arose.

My headlamp is no longer working and the high-beam indicator stays on at all times?? (headlamp is good).
I checked the diagram here:
http://www.scooterhelp.com/electrics/wiring/VSX1T.USA.after.pdf
after checking the harness from front to back. no cuts, shorts, nothing. It looks like it may be a ground issue.
That diagram shows two ground points (center diagram slightly below and to the right of the "junction block under horncast").
Are there some frame ground points I am missing? There's one at the stator (black) rectifier (black), and???
I see no other ground point other than on the speedo which looks to me like there should be another frame ground point.
Anyone know where else there might be another ground point?

comments? point, laughing?
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Hooked
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Hooked
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Check the black wire from lamp holder back to hi beam indicator and ignition switch, this is the lamps earth.
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Ossessionato
'20 300GTS Super Tec '09 250 GTSie '75 Rally 200 '79 P200 '09 Stella 221
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Ossessionato
@willie_b avatar
'20 300GTS Super Tec '09 250 GTSie '75 Rally 200 '79 P200 '09 Stella 221
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Posts: 2610
Location: Midway, Kentucky
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Sounds as if your wires going to the headlamp are reversed. I recently bought a '79 P200 that had seen some creative wiring reformed in the past. I experienced the same thing and found that the high beam and low beam wire had been reversed. The factory headlight plug on mine was history and there were crimp on connections.
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Hooked
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This one has the factory harness / headlamp connector and this issue just showed up suddenly.
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Molto Verboso
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Molto Verboso
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Re: 81 P200 harness ground headlamp issue.
nimar wrote:
strange problem just arose.

My headlamp is no longer working and the high-beam indicator stays on at all times?? (headlamp is good).
I checked the diagram here:
http://www.scooterhelp.com/electrics/wiring/VSX1T.USA.after.pdf
after checking the harness from front to back. no cuts, shorts, nothing. It looks like it may be a ground issue.
That diagram shows two ground points (center diagram slightly below and to the right of the "junction block under horncast").
Are there some frame ground points I am missing? There's one at the stator (black) rectifier (black), and???
I see no other ground point other than on the speedo which looks to me like there should be another frame ground point.
Anyone know where else there might be another ground point?

comments? point, laughing?
What firekdp said. From fading memory, there is a flat tab for a spade connector affixed to the speedo that I think is the black wire ground point shown on the diagram. The other frame grounds are in the fuel tank cavity. A black wire runs from there to the horn cast junction box, then up to the headset to provide grounding. Using a jumper wire with alligator clips to provide grounding can help.

Operating the bright/dim switch should make the high beam indicator turn on/off. Look closely at it. It connects regulated AC from the purple wire to either high/low.

Does your horn blow okay? It uses a ground when pushed.

Back at the voltage regulator, if you can remove and identify which purple wire on an A terminal goes to the bright/dim switch, you can feed + battery voltage to it and the headlight should burn bright/dim. That makes troubleshooting easier. The other purple wire goes to the stator. Do NOT reverse feed the stator coil. It will make a funny noise, possibly move the flywheel and could be destroyed by excess battery current. An inline fuse will keep you out of trouble.
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Hooked
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[SOLVED] Re: 81 P200 harness ground headlamp issue.
All,

I tore the scoot apart. I found no grounds to the frame in the fuel tank cavity (someone else mentioned that off forum as well).

What I did end up finding (thanks blackbart) was a ground wire broken near the spade conn to the speedo. wire was broken inside the insulation and making intermittent contact. I ran a new ground wire from the speedo to the Hi-beam indicator, to the headlamp.

All is well in scootville.

Thanks!

-N
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