Last Thursday as I was leaving a local car gathering I had a very strange problem with my 65. I turned on the lights and tried to rotate the headlights open. Both lights opened half way and stopped. For the record I completed a complete restoration on this car three years ago including a new wiring harness. When I tried to rotate the lights open or closed nothing happened. Then I noticed that both turn signal indicator lights were on as well as the high beam indicator. The "lights" warning light was not on even with the headlight buckets only half open. It was not completely dark, so I decided to drive home and deal with the problem the next day. While driving home, I noticed that every time I stepped on the brake the headlights went out. Let off the brakes, the lights come back on. There was no indication on the volt meter that suggested a short and sudden voltage draw. The next day I started by closing the headlight buckets using the small wheel on the shafts. When I did that, I tried the headlight switch and everything worked as normal. I opened and closed the lights ten times with no problems. Thinking about the problem, I started with the turn signal switch because I know that the brake lights and turn signals all run through there. All of the wiring checked out fine there. Then I could not understand how that switch could cause the headlights to go out. I then checked the emergency flasher ****. My car is a very late 65 and it has the 66 style flasher **** below the dash. I don't know if it was delivered that way or not, but my 65 wiring harness had all of the wires that go to that system so I hooked it up and it tested fine. When I pushed on the flasher ****, it seemed to go it just slightly. I then pulled it out and pushed it back in several times. Bingo, the problems all went away and everything works fine again. Now I can't reproduce the problems. The headlights and flashers all work just fine. Has anyone else had a problem with their emergency flashers causing headlight problems?

Doc

 

It may never show up again, but you didn't fix it by moving the flasher switch. The headlight voltage has nothing to do with the brake voltage, etc. What you describe is a loose ground which opened up and allowed voltage to flow in directions not desired. Stepping on the brake and another electrical item changing is a typical bad ground somewhere, More likely around the source (battery cable ground, starter ground, etc)
PS, most of the things you mentioned would be affected by the ground at the front for the headlights and motors. If the ground wires were still connected together but lost chassis ground, you would get all kinds of strange crossovers. Take a look at the ground screw up front.

 

Thanks, I will do that. I agree that moving the flasher switch did not fix anything.

Doc