The Ford Barn

dtcme99 · 06-19-2024, 02:22 PM

My 29 Model A Roadster Pickup was frame off build by my Father in law. It was part of my wife's inheritance and I've been working on it for a year, or I should say learning about Model A's for a year. I recently completed overhauling the brakes.

My issue now is the headlight brightness. The drivers side lamp works fine. The passenger side is very dim. I replaced the lamp socket and used a new bulb. No matter what I do, nothing gets better. Is there a chance the headlight wiring maybe defective or wired in series instead of parallel?

I'm still learning about the positive ground system, so any help would be much appreciated.

My 1970 Olds Cutlass 442 is easy for me, the 29 gives my headaches.

Thanks,

J Franklin · 06-19-2024, 02:42 PM

Maybe the socket has a bad ground.

nkaminar · 06-19-2024, 03:15 PM

Set your multi meter on DC volts. It will probably be a 20 volt scale. Run some needles or pin through the wires that are connected to the bulb in a place that you can have access to and that will not short to ground. keep the bulb inserted. Turn on the lights and measure the voltage at the pins with respect to a ground not at the light bucket, like a bright and shinny engine bolt or nut. If you get full voltage then you have a bad ground. Trace the ground circuit for the light and clean and tighten any connections. Sometimes the head light bucket has a bad ground. It is grounded at the mount for the bucket. If that is the case then you can take it apart and clean up all the parts, removing any rust or contamination.

If the voltage is low at the pins then there is something wrong with the wiring.

Charlie Stephens · 06-19-2024, 04:46 PM

My guess is that you have a ground problem. A good place to look is painted surfaces that should have been scraped. Maybe the headlight bucket to headlight bar interface. Run a wire from the grounded terminal of the battery to the headlight socket and see if the bulb gets bright, if it does work back from there.

Another thought, any chance your new bulb is designed for 12 volts? Try switching bulbs between the two lights.

Charlie Stephens

Clem Clement · 06-19-2024, 07:09 PM

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bring a ground wire directly from the battery to the headlight. light should britten. Then chase grounds. The cup on the head light bar can be full of paint. clean

06-19-2024, 02:22 PM	#1
dtcme99 Junior Member Join Date: Jun 2024 Posts: 1	Headlight is very dim on 29 Model A Roadster Pickup My 29 Model A Roadster Pickup was frame off build by my Father in law. It was part of my wife's inheritance and I've been working on it for a year, or I should say learning about Model A's for a year. I recently completed overhauling the brakes. My issue now is the headlight brightness. The drivers side lamp works fine. The passenger side is very dim. I replaced the lamp socket and used a new bulb. No matter what I do, nothing gets better. Is there a chance the headlight wiring maybe defective or wired in series instead of parallel? I'm still learning about the positive ground system, so any help would be much appreciated. My 1970 Olds Cutlass 442 is easy for me, the 29 gives my headaches. Thanks,

06-19-2024, 02:42 PM	#2
J Franklin Senior Member Join Date: May 2010 Location: Oregon Posts: 6,370	Re: Headlight is very dim on 29 Model A Roadster Pickup Maybe the socket has a bad ground.

06-19-2024, 03:15 PM	#3
nkaminar Senior Member Join Date: Jan 2012 Location: Western North Carolina Posts: 5,863	Re: Headlight is very dim on 29 Model A Roadster Pickup Set your multi meter on DC volts. It will probably be a 20 volt scale. Run some needles or pin through the wires that are connected to the bulb in a place that you can have access to and that will not short to ground. keep the bulb inserted. Turn on the lights and measure the voltage at the pins with respect to a ground not at the light bucket, like a bright and shinny engine bolt or nut. If you get full voltage then you have a bad ground. Trace the ground circuit for the light and clean and tighten any connections. Sometimes the head light bucket has a bad ground. It is grounded at the mount for the bucket. If that is the case then you can take it apart and clean up all the parts, removing any rust or contamination. If the voltage is low at the pins then there is something wrong with the wiring. __________________ A is for apple, green as the sky. Step on the gas, for tomorrow I die. Forget the brakes, they really don't work. The clutch always sticks, and starts with a jerk. My car grows red hair, and flies through the air. Driving's a blast, a blast from the past.

06-19-2024, 04:46 PM	#4
Charlie Stephens Senior Member Join Date: May 2010 Location: Southern California Posts: 7,305	Re: Headlight is very dim on 29 Model A Roadster Pickup My guess is that you have a ground problem. A good place to look is painted surfaces that should have been scraped. Maybe the headlight bucket to headlight bar interface. Run a wire from the grounded terminal of the battery to the headlight socket and see if the bulb gets bright, if it does work back from there. Another thought, any chance your new bulb is designed for 12 volts? Try switching bulbs between the two lights. Charlie Stephens

06-19-2024, 07:09 PM	#5
Clem Clement Senior Member Join Date: May 2010 Location: Fairfax, VA Posts: 3,532	Re: Headlight is very dim on 29 Model A Roadster Pickup Sponsored Links (Register now to hide all advertisements) bring a ground wire directly from the battery to the headlight. light should britten. Then chase grounds. The cup on the head light bar can be full of paint. clean