Low beam socket has voltage, but no light

[sevesteen]

One of the few problems with my new GL1000 is that the low beam headlight doesn't work. Has a Vetter fairing. High beam works, and when I put a voltmeter on the low beam terminal with no bulb, it shows just under 12 volts with the engine off, same as the high beam. Tried a different bulb. Tested the headlight by hooking it to a battery with alligator clips, both high and low beams worked. With the headlight hooked up properly, no light, no voltage. I was hoping it was something with the socket, so a round meter probe made contact, but a flat headlight terminal didn't...so I stuck one terminal from the headlight into the low beam socket and measured (with the other two still disconnected) and got voltage.

Where do I check next?

 

[dan filipi]

Check the ground in the headlight plug.
Try a jumper ground from the battery to it.
If it lights then it's something to do with a bad ground.

 

[sevesteen]

dan filipi » Sun Aug 18, 2013 9:18 am[/url]":by22b0l1]
Check the ground in the headlight plug.
Try a jumper ground from the battery to it.
If it lights then it's something to do with a bad ground.

If it was a ground problem, wouldn't it affect the high beam as well?

 

[dan filipi]

Well if you have +12 at the plug the only thing left is lack of ground.
Weak or no ground can do strange things.

 

[sevesteen]

Did some more troubleshooting this morning--there's something wrong in the wires that connect the fairing to the bike. Using a turn signal as a test light, low beam socket directly to the battery will not light, high beam will. Unplugged the socket from the fairing, got the same from the appropriate terminals to the battery--voltmeter had 12 volts, test light would light on running lights and high beam pins, but not the low beam.

The original headlight socket is still there, and I was able to get my hand in and attach the test light--That works with the test light. Does anyone have a reference to where the fairing wiring connects to the bike? I'm guessing I will have to take the Windjammer off to get the tank sides off to see where things go.

 

[brianinpa]

Sometimes the connections of the electrical harness from the bike to the fairing can be somewhat suspect. I was having problems when I first got my bike and had to take the fairing off and wound up redoing everything as far as connecting the harness to the bike. The PO just used wire splices for everything so I cut it all and soldered all connections to make sure I didn't have any other problems. Everything should be up front. If the stock headlight bucket is still there, that is where the connections are made. Just find the correct wire for left/right turn signals, high/low beam and the running lights. Take a look at page 3.

https://www.craigvetter.com/images/...mages/Windjammer_instructions/1979 GL1000.pdf

 

[sevesteen]

brianinpa » Sun Aug 18, 2013 11:12 am[/url]":3hbln6y3]
Sometimes the connections of the electrical harness from the bike to the fairing can be somewhat suspect. I was having problems when I first got my bike and had to take the fairing off and wound up redoing everything as far as connecting the harness to the bike. The PO just used wire splices for everything so I cut it all and soldered all connections to make sure I didn't have any other problems. Everything should be up front. If the stock headlight bucket is still there, that is where the connections are made. Just find the correct wire for left/right turn signals, high/low beam and the running lights. Take a look at page 3.

https://www.craigvetter.com/images/...mages/Windjammer_instructions/1979 GL1000.pdf

Bingo! Wire splices (as indicated in the Vetter manual). Soldered the low beam wire from the fairing harness to the factory low beam light, works great.

Thanks, all! Made it much easier than figuring this out on my own

 

[slabghost]

I love it when stuff gets fixed!

 

[brianinpa]

sevesteen » Sun Aug 18, 2013 12:30 pm[/url]":1d7903dt]

brianinpa » Sun Aug 18, 2013 11:12 am[/url]":1d7903dt]
Sometimes the connections of the electrical harness from the bike to the fairing can be somewhat suspect. I was having problems when I first got my bike and had to take the fairing off and wound up redoing everything as far as connecting the harness to the bike. The PO just used wire splices for everything so I cut it all and soldered all connections to make sure I didn't have any other problems. Everything should be up front. If the stock headlight bucket is still there, that is where the connections are made. Just find the correct wire for left/right turn signals, high/low beam and the running lights. Take a look at page 3.

https://www.craigvetter.com/images/...mages/Windjammer_instructions/1979 GL1000.pdf

Bingo! Wire splices (as indicated in the Vetter manual). Soldered the low beam wire from the fairing harness to the factory low beam light, works great.

Thanks, all! Made it much easier than figuring this out on my own

I never trust PO electrical work and splicing jobs. You know that there was one problem, so now when you have another, look for the splices and that is usually the first thing that needs to be fixed. As you are working on one thing, if you find a splice for another part, fix that while you are there. It won't be long before all the old stuff is out of the way and you will know that the harness is back to as good as you can get it.

 

[sevesteen]

brianinpa » Sun Aug 18, 2013 7:19 pm[/url]":1kl23963]

I never trust PO electrical work and splicing jobs. You know that there was one problem, so now when you have another, look for the splices and that is usually the first thing that needs to be fixed. As you are working on one thing, if you find a splice for another part, fix that while you are there. It won't be long before all the old stuff is out of the way and you will know that the harness is back to as good as you can get it.

I doubt it is PO electrical work, I think it was Original Dealer work from 1978. But you're right, I don't trust the remaining splices, and next time I'm in that area I'll improve them.