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Lighting issues please help!

Charging System, Wiring, Lighting
CL77butcher
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Location: Connecticut

Lighting issues please help!

Post by CL77butcher » Fri Apr 22, 2011 8:15 pm

I just finished building the tail light and jerry-rigging a 35/35 halogen into the old housing for a headlight. I bench tested both and everything worked well. I got them installed on the bike and plugged in the same battery (known good). My LED tail light works properly but my headlight will not come on at all. I tried all switch positions at the key, hi/ lo beam switch, and at the headlight housing, no combination will turn on the headlight.
I disconnected the battery and broke out my multimeter I connected one lead to the center terminal of the rectifier and used the other to check the bullet connectors up front. I got continuity (diode check=beeeeeep) on every terminal. I considered the direction of current flow and swapped the meter leads, same result. I looked at the schematic and followed the SCR diagram, am I nuts or is that a good sign of a shorted SCR? I have never seen a diode circuit go bad as a short before I am used to a bad diode presenting an open. This is my first time playing with a SCR like the one on this bike though and wanted to check with the pro's.

Please let me know if I am going nuts or if this is just a 60's honda thing. I welcome any suggestions as to what is preventing my headlight from working.

CL77butcher
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Joined: Thu Jan 13, 2011 10:14 am
Location: Connecticut

@#$

Post by CL77butcher » Fri Apr 22, 2011 9:23 pm

Ok so the SCR is not the problem. I am getting continuity through the new headlight. Still wondering why I'm not getting any light out of it though. Any ideas?

Eljeef
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Post by Eljeef » Fri Apr 22, 2011 11:21 pm

Is your jerry-rigged light grounding well? I know my headlight bulb fooled me for awhile and it turned out to be tough to ground.
1964-C77 305 Dream
2002 BMW R1150GS

Eljeef
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Post by Eljeef » Fri Apr 22, 2011 11:22 pm

Is your jerry-rigged light grounding well? I know my headlight bulb fooled me for awhile and it turned out to be tough to ground.
1964-C77 305 Dream
2002 BMW R1150GS

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brewsky
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Re: Lighting issues please help!

Post by brewsky » Sat Apr 23, 2011 4:38 am

CL77butcher wrote:I have never seen a diode circuit go bad as a short before I am used to a bad diode presenting an open.
I have....here's what they look like:
Note there is no fuze between the hot battery terminal and the rectifier, so if it does short...it is not good!
Attachments
Burned Rectifier111.JPG
66 dream, 78 cb750k, 02fz1, 09 wing

Wilf
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Post by Wilf » Sun Apr 24, 2011 9:23 am

That would be a Selenium Rectifier, not an SCR (Silicon Controlled Rectifier), which is an entirely different animal.

Wilf

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brewsky
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Post by brewsky » Sun Apr 24, 2011 10:08 am

Wilf wrote:That would be a Selenium Rectifier, not an SCR (Silicon Controlled Rectifier), which is an entirely different animal.

Wilf
Sorry about that...wasn't up on the SCR abbreviation...thought maybe it was "selenium controlled rectifier"
66 dream, 78 cb750k, 02fz1, 09 wing

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