Diagnosing headlights inoperable- yes another one
04-16-2014, 12:19 PM
#1
Le Mans Master
Thread Starter
Diagnosing headlights inoperable- yes another one
My headlights were intermittent when I bought the car but did function when I drove it home after some "tapping and shaking"
I'm getting my new motor gears and have the headlight motors rebuilt to go back in, thought it was a good time to get my headlights running.
Backstory:
All my parking lights work properly. Two days ago my RHS headlights burned with the bucket rolled shut (motors out). No passenger side lights.
Corroded contacts look nasty every time I open a connection on the forward harness, I have been cleaning. Now I have NO headlights whatsoever and can coax a meager 10.6 volts out of the low beam side of the PS plug AT THE HEADLAMP ITSELF (I have not pulled the DS yet)
I get no voltage on the high beam plug of the low beam lamp, even when I removed the spade connector from the plastic.
I just pulled my dimmer switch which I understand feeds the whole thing, it is as follows:
1) Is this a good profile for the dimmer? Basically I expected the tan side to have continuity the whole time on either setting, but I only seem to have continuity on low beams. Pole A is the ground. The ground pole on the dimmer was VERY corroded, as if it had water on it. The other two poles were much better. I've cleaned them.
A few questions: 2) would my low beam not burn at the 10.6 volts at the plug? It does not. The filament is not obviously bad (thought I suppose I could pull the other low beam and swap them, at least it was working the other day). Note I am running on the tan and black wires to the lamp, I removed the green strip space connector and pushed it aside for the moment.
3) why does my AIM show only a green stripe and black (ground) wires (two wires) going to my high beam side from my low beam lamp? I have four wires! I admit they are two sets of green strip and ground. All the harness looks old and correct no splicing. My car is a Dec 1963 build
4) is my pull switch for the lights serviceable or sealed?
I'm sorry if a few of these questions precede my further investigation but I couldn't stand not asking... thanks as always!
I'm getting my new motor gears and have the headlight motors rebuilt to go back in, thought it was a good time to get my headlights running.
Backstory:
All my parking lights work properly. Two days ago my RHS headlights burned with the bucket rolled shut (motors out). No passenger side lights.
Corroded contacts look nasty every time I open a connection on the forward harness, I have been cleaning. Now I have NO headlights whatsoever and can coax a meager 10.6 volts out of the low beam side of the PS plug AT THE HEADLAMP ITSELF (I have not pulled the DS yet)
I get no voltage on the high beam plug of the low beam lamp, even when I removed the spade connector from the plastic.
I just pulled my dimmer switch which I understand feeds the whole thing, it is as follows:
1) Is this a good profile for the dimmer? Basically I expected the tan side to have continuity the whole time on either setting, but I only seem to have continuity on low beams. Pole A is the ground. The ground pole on the dimmer was VERY corroded, as if it had water on it. The other two poles were much better. I've cleaned them.
A few questions: 2) would my low beam not burn at the 10.6 volts at the plug? It does not. The filament is not obviously bad (thought I suppose I could pull the other low beam and swap them, at least it was working the other day). Note I am running on the tan and black wires to the lamp, I removed the green strip space connector and pushed it aside for the moment.
3) why does my AIM show only a green stripe and black (ground) wires (two wires) going to my high beam side from my low beam lamp? I have four wires! I admit they are two sets of green strip and ground. All the harness looks old and correct no splicing. My car is a Dec 1963 build
4) is my pull switch for the lights serviceable or sealed?
I'm sorry if a few of these questions precede my further investigation but I couldn't stand not asking... thanks as always!
Last edited by ChattanoogaJSB; 04-16-2014 at 12:22 PM.
04-16-2014, 12:40 PM
#2
Melting Slicks
Did you check the outboard firewall connector beneath the master cylinder? I believe the headlight, and motors wiring go thru that connection. If you decide to check there, be very careful with the plastic clips that hold the connector......VERY FRAGILE.
04-16-2014, 12:48 PM
#3
Le Mans Master
Thread Starter
That's a good thought, I have pulled them several times and the contacts all look good; maybe I need to attack them with my multitester and see what voltage I have on the high/low circuits there! I'm not an electrical expert, obviously, but I can find my way through...
04-17-2014, 10:18 AM
#5
Le Mans Master
Thread Starter
Just as a follow up, and with my thanks to the forum as always:
The headlights work. I had a very badly corroded connector at the PS pigtail and that helped get the voltage up on the passenger side (the one that gave me trouble most). After I cleaned the dimmer switch contacts, I got almost 11.5 volts to the headlamp bulb socket itself, with the engine off and the car not having been driven for a week or so. Turns out, both low beams were burned out (go figure), so I installed two new ones, and did the slight modification where I put a jumper between the low and high side of the low beams, and removed and taped off the high beam lead on the low beam light (the black/green wire, as a recent contributor did to raise the light level on the low beams).
The change in brightness is considerable with the jumper, I can vouch for that.
By the end of the day all my contact cleaning left me with two bright low beams (I still need to replace the high beams, but now I'm driving in all conditions!).
On another note, importantly, I got my two new headlight motor gears from ZIP; Frankie was right, there was no modification needed to them. If the old reproductions were slightly out of spec, I found these to be dead ringers for the originals except that the sharp edges now come with a nice small bevel, probably will prevent any minute shavings from forming in the gear house.
To lower the torque required to get the motors turning, I was planning on installing a different spring washer with a thinner flat washer underneath which has been written up here before. But first, I installed the new gear WITH the OEM spring washer (the black one) and WITHOUT ANY flat washer underneath. I assembled and tested to see if the motor would spin free without the flat washer riding below the spring washer. I reasoned if this was true then the headlight bucket would be free to creep open at high speed perhaps. I was unable to turn the motor with a large flat screwdriver in the new gear where the headlight bar goes- could not budge it. I'll have to take a test drive, but the lack of the flat washer has reduced the effort the motors take to turn the bucket open, but the bucket has a nice firm open and close! So far I'll call this a success!
With a good cleaning inside the housing and some white lithium grease lightly on the gears, the thumb wheel now turns smoothly without wear on the fingers!
In the video, you notice I can slightly rock my PS headlight bucket when I close them- that is only because I didn't let it run long enough to reach full close, as my PS closes just ever so slightly slower than the DS. It's now tight!
So unless these guys fly open at speed, I'm going to recommend you guys try leaving out the washer under the spring washer entirely!
Enjoy your morning! I know I will!
View My Video
The headlights work. I had a very badly corroded connector at the PS pigtail and that helped get the voltage up on the passenger side (the one that gave me trouble most). After I cleaned the dimmer switch contacts, I got almost 11.5 volts to the headlamp bulb socket itself, with the engine off and the car not having been driven for a week or so. Turns out, both low beams were burned out (go figure), so I installed two new ones, and did the slight modification where I put a jumper between the low and high side of the low beams, and removed and taped off the high beam lead on the low beam light (the black/green wire, as a recent contributor did to raise the light level on the low beams).
The change in brightness is considerable with the jumper, I can vouch for that.
By the end of the day all my contact cleaning left me with two bright low beams (I still need to replace the high beams, but now I'm driving in all conditions!).
On another note, importantly, I got my two new headlight motor gears from ZIP; Frankie was right, there was no modification needed to them. If the old reproductions were slightly out of spec, I found these to be dead ringers for the originals except that the sharp edges now come with a nice small bevel, probably will prevent any minute shavings from forming in the gear house.
To lower the torque required to get the motors turning, I was planning on installing a different spring washer with a thinner flat washer underneath which has been written up here before. But first, I installed the new gear WITH the OEM spring washer (the black one) and WITHOUT ANY flat washer underneath. I assembled and tested to see if the motor would spin free without the flat washer riding below the spring washer. I reasoned if this was true then the headlight bucket would be free to creep open at high speed perhaps. I was unable to turn the motor with a large flat screwdriver in the new gear where the headlight bar goes- could not budge it. I'll have to take a test drive, but the lack of the flat washer has reduced the effort the motors take to turn the bucket open, but the bucket has a nice firm open and close! So far I'll call this a success!
With a good cleaning inside the housing and some white lithium grease lightly on the gears, the thumb wheel now turns smoothly without wear on the fingers!
In the video, you notice I can slightly rock my PS headlight bucket when I close them- that is only because I didn't let it run long enough to reach full close, as my PS closes just ever so slightly slower than the DS. It's now tight!
So unless these guys fly open at speed, I'm going to recommend you guys try leaving out the washer under the spring washer entirely!
Enjoy your morning! I know I will!
View My Video
04-17-2014, 10:53 AM
#6
Team Owner
Very nice operation vis a vis the video....that's about as good as it gets