Brake lights not working

Yes they need to be mounted to get a ground.

Well, son of a.....gun. I spent all day killing myself trying to figure out what the problem was, and all along it was because I didn't attach the brackets first. 🤬

I'm going to try hook up everything again tomorrow.
 
Did I make a mistake by not attaching the taillight housing and bracket to the fender before wiring and testing them? Do the bracket bolts act as a ground for the lightbulbs?
Yes they do, sorry I didn’t make that clear. On the other hand, you figured that out yourself! Good job!
 
A team,

You did a good job with the volt meter. It is really good to learn to use them correctly. A lot of electrical problems can be solved with it.

It is also good to learn some electrical theory. One is that the electrical circuit is a complete loop. The current starts at the battery and ends up back at the battery. If there is an open part of the loop anywhere the system will not work.

Thank you very much for posting the solution. We Barners learn that way, even us old guys who were around in the beginning.
 
Well, son of a.....gun. I spent all day killing myself trying to figure out what the problem was, and all along it was because I didn't attach the brackets first. 🤬

I'm going to try hook up everything again tomorrow.

A past friend of my mine spent hours checking why his head lights didn’t work, his wife came out and stated do you think both bulbs are burnt out? Tom said light bulbs don’t burn out at the same time……………LOL Tom replaced both head lights!!!!!!!
 
It was definitely frustrating to learn it was something so minor in the end, but it was definitely a learning experience and you guys definitely helped me to solve the problem in the end (as usual).

Thanks as always, and hopefully I won't have to post another thread for awhile. 🙏

Here's a couple of pics of the brake lights activated (I forgot to take a picture of the taillights). Ignore the tire cover. That was my father's store that closed in 2001. I don't remember if he painted the graphic on there, or if my sister did it, but he kept it on the spare tire from the late 70s until he started restoring it 15 - 20 years ago. I put it back on there for nostalgia and for my father.
 

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Way back in #4 there was mention of a bad ground. But at least its now fixed.
Yes, and I mentioned it again in post #12. When dealing with electricals, I always check for good grounds before proceeding. The little e-guys want to make a complete path back to the battery. They will take the easiest path and not always the path you intended...


I just wish they said that in the mechanics handbook, instead of just giving the wiring diagram.

The ground is shown in the wiring diagram. :p

521773
 

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Yes, and I mentioned it again in post #12. When dealing with electricals, I always check for good grounds before proceeding. The little e-guys want to make a complete path back to the battery. They will take the easiest path and not always the path you intended...

The ground is shown in the wiring diagram. :p

521773

I was probably thinking of a grounding wire like in a house circuit when I saw that. 🤦
 
I ran into an odd electrical problem like this a few years ago while making a Model A streetable that had been an amateur messtoration, complete with the expected shortcomings. A local special interest car place called and asked me to make the dual tail and brake lights work. No matter what their in-house mechanic did, he couldn't get them to work, even after replacing the entire lighting harness and changing bulbs numerous times. I, too, ran into a brick wall for a while until I happened to notice while on my back for the umpteenth time that the underside of the rear fender above me had an odd surface. Not shiny, but kind of crinkly. Sure enough! The beautifully painted rear fender on top was made of FIBERGLASS! No WONDER the rear lights and brake lights wouldn't work! Fiberglass is non-conductive, so there was no grounding ability. I ran a wire from a tailight mounting stand bolt on each side to a good ground spot on the chassis and viola! Let there be light! Another head scratcher solved.
Next time you encounter such a problem with someone else's Model A, ensure that the rear fenders are Henry's STEEL and that the taillight stand has a good ground against the rear fender surface.
Marshall
 
Early electrical systems for houses had one wire with the return path being the ground. Same for early phone systems. Dirt is not very conductive, but if wet and enough of it, it will conduct enough current.
 
I ran into an odd electrical problem like this a few years ago while making a Model A streetable that had been an amateur messtoration, complete with the expected shortcomings. A local special interest car place called and asked me to make the dual tail and brake lights work. No matter what their in-house mechanic did, he couldn't get them to work, even after replacing the entire lighting harness and changing bulbs numerous times. I, too, ran into a brick wall for a while until I happened to notice while on my back for the umpteenth time that the underside of the rear fender above me had an odd surface. Not shiny, but kind of crinkly. Sure enough! The beautifully painted rear fender on top was made of FIBERGLASS! No WONDER the rear lights and brake lights wouldn't work! Fiberglass is non-conductive, so there was no grounding ability. I ran a wire from a tailight mounting stand bolt on each side to a good ground spot on the chassis and viola! Let there be light! Another head scratcher solved.
Next time you encounter such a problem with someone else's Model A, ensure that the rear fenders are Henry's STEEL and that the taillight stand has a good ground against the rear fender surface.
Marshall


Marshall, good for you. I cant imagine how frustrating that might have been. If that were me, I would still be under the car scratching my head.
 
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