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lclark0624

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I have a simple problem with ny '75 B. The headlights work fine in low beam, but both headlights go out when switched to high beam. Any ideas?
 
I have a '75 B as well. When I flip on my brights, there's a brief nanosecond when I have no headlights at all. Seems to only happen when I flip them on though, not when I switch back to low beams.

Repeat after me...
We shall not question Lord Lucas.
We shall not question Lord Lucas.
We shall not question Lord Lucas.
/ubbthreads/images/graemlins/devilgrin.gif
 
atleast you get brights!

Ok lord lucas, no more questions and the top stays down even in the rain.

actually, i was driving a new 66 midget through the california farm fields up 99 with the top down. cloudy, but no rain. suddenly the sky opened up with a monsoon drenching everything. it seemed every drop of rain in the san joaquin valley was aimed at my head. i was fine until the unfinished freeway ended and i had to stop at a red light in atwater. i thought i'd drown until i found a gas station i could pull under the canopy to get the top up. even wet it was fun.
 
lclark, I've had that happen to me twice now. 45mph+ and you can stay dry as popcorn. Anything much less or heaven forbid, a stoplight or sign and it's WET!
 
Yes it was wet.

Thanks for the tip, sultanoswing. I've added it to my favorites and it my next stop on the information freeway. pray for no rain.
 
FWIW: I have re-drawn every MGB wiring diagram I could find to make them easier to read, and I have drawn them with color coded wiring. All in all, I have redrawn 32 diagrams, including the MGBV8 and the MGC. These should be a big help in solving problems like this.

You can download them for free at https://www.advanceautowire.com Just click on the "stock schematics" button. Take the PDF file to Kinkos, staples, etc, and have them print your particular diagram as large as you need on their color printer.

Feel free to copy these diagrams and pass them around to your friends. Pass the word around that these are available. Hopefuly, these will help us keep the smoke in the wires where it belongs!
 
Each bulb has two filaments, one for high beam and one for low. It's possible that both high beams are burnt out. Remove a bulb and diconnect the plug. there are three wires, one for ground (should be black), one for high beam and one for low. With a test light, test the wries for current.
 
Wire legend: blue w/white for high, blue w/red for low (beam)...
but if they both come on after switching from low to high then back, the bulbe are not the issue. It's a dicky switch. The headlamps aren't fused and consequently the current load onna switch causes pitting and resistance in it. Fiddlin' it about in the "high" position usually achieves the desired lighting... the switch CAN be disassembled and serviced, but if you don't wanna be a victim of the Prince of Darkness, R&R the durned thing. It's only money /ubbthreads/images/graemlins/wink.gif

"Your MONEY, or your LIFE!" sayeth th' Prince.
 
OR: You could go with danmas' tricky li'l relay box conversion...

but I prefer to "keep my car all GM."... so to speak.
 
Bah - it's not tricky - but it is a lot of fun having nice bright, reliable lamps! /ubbthreads/images/graemlins/smile.gif
 
No argie-bargie 'bout it bein' tricky... just have no "good intel" onna skill level of the owner in the dilemma.

Hereforewith sultanofswing will be regarded as a ~survivor~!!!

BTW: You onna North or South island?

Edit: Check yer PM's!
 
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