Where did all my lights go?

[joeypoconos]

Had a great time tonight at a local cruise in. When I started my 29 Sport Coupe to leave for home I went through my usual ritual of checking the lights. Brights work, dims work, cowl lights work, tail light and brake lights work. Time to head for home. About 2 miles from home the high beams quit. I set the switch to the first notch and the low beams came on. A few minutes later they quit. Tried the left switch position and the cowl lights came on. After a minute or less they went out. Now I'm driving home without head or cowl lights. Tail and brake lights working fine. Oh boy,do I wish I could drive her home in reverse.
Made it home ok, but no amount of finagaling with the light switch does anything.
Any suggestions ????

[J Franklin]

Check the bulb filaments and if they are gone you most likely lost significant ground. I had a bad ground just on a taillight once and replaced the bulb often untill I did something about it. Check the battery cable for looseness and both connections with an Ohm meter to ground and also the sockets to ground. One of our club members brought in a woven ground strap that did not have continuity but looked fine, it was amazing. I took it apart at the battery side and there was green copper sulfide under the crimp to the mesh completely making an effective block to ground!

[Bruce Adams]

Just a shot, LITERALLY IN THE DARK, but if you have a generator and a bad ground in your system, the gen will go ape and create a high voltage which will blow your bulbs as called on.

[joeypoconos]

Thanks for the tips. Will be checking for loose/bad ground. Just wondering why the tail/brake lights (they are led's), and a third led brake light I installed some time ago, still work and everything else went kaput.
More to follow.

[Bruce Adams]

Their filaments are probably much thicker and their output lower so they were not victims. I have successfully used 12 volt LEDs on my 6 volt car, so maybe they are able to handle higher voltages than incandescents.
Hesdlights are nortorious for going VERY BRIGHT like an exploding star when operating with a generator and poor ground condition. I do not know why the cowl lamps were different than the tailites, though. Do the brake lights still work?

[Mitch//pa]

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start at the end of the juice.... ck for powers and grounds at the sockets and work your way back

[joeypoconos]

Bruce - yes, brake lights still work. That includes one of those LED third brake lights that mount to the rear window. Very perplexing problem

[J Franklin]

Maybe you didn't use the brakes when the ground was acting up.

[jrelliott]

Leds will tolerate voltage spikes better than bulbs. There is no filament in a LED to burn out, by running them at higher than rated voltage will reduce the service life, but that is negligable considering how long the leds will run. By increasing the voltage across a LED was one of the ways the led in your DVD, or other devices use to keep working as they age. They get weaker output as they run for extended times.

[Tom Wesenberg]

Any interuption in the charging circuit will allow an unregulated generator to put out high voltage. The charging circuit includes the generator, cutout. ammeter, and battery (also fuse, if you installed one) and all the wires and connections to these parts. Check the charging circuit for a fault.

[joeypoconos]

First, I have only basic knowledge of electricity so please bare with me. With the car not running, ignition key on and fuse installed i ran some checks with my multiimeter (confuses the heck out of me). Battery putting out approximately 6V. Battery to starter terminal 6V. Starter terminal to fuse 6V. Fuse to generator cutout 6V. Now here's where it gets tricky. I tested circuit from one of the light bulb socket tabs (the thing that the bulb sits on) and got approximately 6V reading. The other gave no reading. Performed same test on other head light with same results. Ran a continuity test from each of the two socket tabs with no reading. When I touched the inside or outside of the socket the continuity reading went to zero. Same on the other h/lite.
Next, I will repeat the above with car running??? Any other thoughts, suggestions, comments. Thanks to everyone for your help.

[Bruce Adams]

Did you remember to switch to Hi, or Lo Beam for the "other" tab?
Not to insult, but it would be something I might forget to do.

[joeypoconos]

Thanks, It never occured to me that one was for hi and other for lo.
I ran tests with the multimeter with car at normal idle. All paths from battery to lights (including ammeter) showed approximately 9V. Ran the continuity test from the light bulb bodies to the bolts that hold the h/lite to the h/lite bar. Meter showed continuity. Kicked up the idle and repeated tests with same results.
My two tail lights and a third brake light are all LED's. They remained lit throughout this process. I'll run some tests on the tail/brake lights and see what happens. For now, I remain STUMPED!

[BILL WILLIAMSON]

9 volts?? seems too high? Bill W.

[joeypoconos]

Re-ran test's with my multimeter. Only anomoly appears to be with the generator. At a fast idle it is putting out a consistent (no flucuations)10 volts. I'll try to back it down via the 3rd brush and see if that helps.

[Bob C]

The third brush will not affect the voltage output. You most likely have a ground problem
or some other loose wires causing the high voltage, battery condition can also affect voltage.

Bob

[joeypoconos]

Thanks Bob - I guess its back to the drawing board.

[BILL WILLIAMSON]

Someone posted that "star" washers of various sizes are grounds "best friends." Bill W.