The Ford Barn

josh1331 · 09-12-2013, 11:50 PM

Being a duff on electrical and doing things the hard way, with and without tester One of my high beams doesn't work. What is the procedure best to check this out please. Wiring is all new. Was working before now on one passenger side light. No high beam. I checked bulbs etc but went no further until I check with my fellow brothers on this web john

ford3 · 09-13-2013, 12:11 AM

check bulb first, then check ground at lite, then round up your trusty test lite, the one with the bulb on the end, check connections at socket, check each wire for juice, if no juice, trace wire back to the main connection at the bottom of steering colom, if necessary run a seperate test hot wire to the socket , you may have a broken wire, just start at the lite and work your way back to the switch

H. L. Chauvin · 09-13-2013, 08:16 AM

Hi josh,

Good rule of thumb: When Model A headlights, tail lights, cowl lights, interior lights, or even trailer lights on a trailer attached to a Model A do not work, about 95% of the problems are a result of a poor ground.

(Your 1331 number used to be an Officer MOS designation for Combat Engineers who were, & still are the Army's Amphibians. They landed on the beaches of Normandy to clear mines & set up a beach-head prior to the arrival of the Infantry -- similar in mission back then & today to the Navy's Marines.)

frank mcdaniels · 09-13-2013, 08:55 AM

Hey Josh, I just had this problem on my roadster this weekend. You really need a test light to trace down the problem. The problem with mine was where the light socket is attached to the head lamp bucket (where the little spring is) was rusty and corroded. Thats where it's getting its ground. Also on my repro bulb socket, which isn't the best quality, the wires that connect to the bulb were touching each other. I made a little plastic shim to go between them and walla , they worked. Hope this helps, Frank

Purdy Swoft · 09-13-2013, 10:05 AM

Probably a ground problem. I usually add extra ground. I use an electric soldering gun and rosin core solder. I solder a wire to the repro socket. I run the extra ground wire through the headlamp conduit,down the inside of the radiator shell and ground under the nut, inside the frame where the front hood latch screw connects.The extra ground wire is well hidden. If you try this be sure to remove paint under the nut where the wire grounds.

pat in Santa Cruz · 09-13-2013, 10:46 AM

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if, by "all new" you mean you replaced the sockets and wires in the buckets, odds are there is the problem. The contact springs in the bulb socket are weak, and allow the contacts to move aside when the bulb is installed. They can ground against the side of the socket, shorting out, or touch each other and cause both filaments to burn simultaneously. I slip a piece of shrink tube over them to insulate them from the sides of the socket. If they are touching each other, Frank McDaniels' solution (stated above) would work.

Likewise, and more commonly, the contacts in the socket at the base of the bucket can move aside when the harness wires are installed, causing shorts and poor contact. In this case I cut the contacts off both wires, pull the bucket wires inside, and thread the harness wires through the spring loaded channels. I still use the plastic spacer to provide spring pressure against the bezel ring. With the harness wires inside the bucket, I hard wire them to the light socket wires, using wire nuts to facilitate removal should it be necessary later on.

jrelliott · 09-13-2013, 11:32 AM

If the low beam works, then it is not a ground problem. Problem is in the connection at the bottom of the headlight bucket or the connection from the bulb socket to the bottom of the bucket if you are using the original set up. Also one of the contacts on the bulb socket could be bad. You can switch bulbs with the other headlight to be sure the bulb is good or just turn it over to insure the other filament is good. Offset filament is the low beam and goes on the top when the bulb is inserted correctly. You will at least rule out the bulb as the problem. The connection at the headlight switch is most likely good since the other high beam works and it is a common connection at the switch. Doubt if the wire from the switch to the headlight is bad since it is a new harness.

09-12-2013, 11:50 PM	#1
josh1331 Senior Member Join Date: May 2010 Location: Charlestown,R.I. Posts: 465	Best way to check why high beam on one light no working Being a duff on electrical and doing things the hard way, with and without tester One of my high beams doesn't work. What is the procedure best to check this out please. Wiring is all new. Was working before now on one passenger side light. No high beam. I checked bulbs etc but went no further until I check with my fellow brothers on this web john

09-13-2013, 12:11 AM	#2
ford3 Senior Member Join Date: Oct 2012 Location: oroville calif. Posts: 1,453	Re: Best way to check why high beam on one light no working check bulb first, then check ground at lite, then round up your trusty test lite, the one with the bulb on the end, check connections at socket, check each wire for juice, if no juice, trace wire back to the main connection at the bottom of steering colom, if necessary run a seperate test hot wire to the socket , you may have a broken wire, just start at the lite and work your way back to the switch

09-13-2013, 08:16 AM	#3
H. L. Chauvin Senior Member Join Date: May 2010 Posts: 4,179	Re: Best way to check why high beam on one light no working Hi josh, Good rule of thumb: When Model A headlights, tail lights, cowl lights, interior lights, or even trailer lights on a trailer attached to a Model A do not work, about 95% of the problems are a result of a poor ground. (Your 1331 number used to be an Officer MOS designation for Combat Engineers who were, & still are the Army's Amphibians. They landed on the beaches of Normandy to clear mines & set up a beach-head prior to the arrival of the Infantry -- similar in mission back then & today to the Navy's Marines.)

09-13-2013, 08:55 AM	#4
frank mcdaniels Senior Member Join Date: May 2010 Location: moorhead minnesota Posts: 167	Re: Best way to check why high beam on one light no working Hey Josh, I just had this problem on my roadster this weekend. You really need a test light to trace down the problem. The problem with mine was where the light socket is attached to the head lamp bucket (where the little spring is) was rusty and corroded. Thats where it's getting its ground. Also on my repro bulb socket, which isn't the best quality, the wires that connect to the bulb were touching each other. I made a little plastic shim to go between them and walla , they worked. Hope this helps, Frank

09-13-2013, 10:05 AM	#5
Purdy Swoft Senior Member Join Date: May 2010 Location: Alabama Posts: 8,099	Re: Best way to check why high beam on one light no working Probably a ground problem. I usually add extra ground. I use an electric soldering gun and rosin core solder. I solder a wire to the repro socket. I run the extra ground wire through the headlamp conduit,down the inside of the radiator shell and ground under the nut, inside the frame where the front hood latch screw connects.The extra ground wire is well hidden. If you try this be sure to remove paint under the nut where the wire grounds.

09-13-2013, 10:46 AM	#6
pat in Santa Cruz Senior Member Join Date: May 2010 Location: santa cruz, calif Posts: 2,011	Re: Best way to check why high beam on one light no working Sponsored Links (Register now to hide all advertisements) if, by "all new" you mean you replaced the sockets and wires in the buckets, odds are there is the problem. The contact springs in the bulb socket are weak, and allow the contacts to move aside when the bulb is installed. They can ground against the side of the socket, shorting out, or touch each other and cause both filaments to burn simultaneously. I slip a piece of shrink tube over them to insulate them from the sides of the socket. If they are touching each other, Frank McDaniels' solution (stated above) would work. Likewise, and more commonly, the contacts in the socket at the base of the bucket can move aside when the harness wires are installed, causing shorts and poor contact. In this case I cut the contacts off both wires, pull the bucket wires inside, and thread the harness wires through the spring loaded channels. I still use the plastic spacer to provide spring pressure against the bezel ring. With the harness wires inside the bucket, I hard wire them to the light socket wires, using wire nuts to facilitate removal should it be necessary later on. Last edited by pat in Santa Cruz; 09-13-2013 at 01:58 PM.

09-13-2013, 11:32 AM	#7
jrelliott Senior Member Join Date: May 2010 Location: Pine, AZ Posts: 823	Re: Best way to check why high beam on one light no working If the low beam works, then it is not a ground problem. Problem is in the connection at the bottom of the headlight bucket or the connection from the bulb socket to the bottom of the bucket if you are using the original set up. Also one of the contacts on the bulb socket could be bad. You can switch bulbs with the other headlight to be sure the bulb is good or just turn it over to insure the other filament is good. Offset filament is the low beam and goes on the top when the bulb is inserted correctly. You will at least rule out the bulb as the problem. The connection at the headlight switch is most likely good since the other high beam works and it is a common connection at the switch. Doubt if the wire from the switch to the headlight is bad since it is a new harness.