• When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.

1967 Charger Headlights Only Open Partially Unless Override/Hold Open Switch is Down

MoparJTH

Member
Local time
3:30 AM
Joined
Dec 13, 2011
Messages
6
Reaction score
1
Location
Redding, CA
Hello everyone!

I've had my 67 Charger since I was 16. Going on 20 years now. Many years ago, I had to go through the whole headlight system because it quit working. Long story short, the little knub on one of the limit switches broke off and during a long drive sent constant power to the motors and burnt them both up... I probably should have suspected something when the "headlamps not open" light came on even though they were open all the way lol. Anyway, I bought rebuilt motors, new limit switches, and got them working cherry again and they've been working great for 10+ years.

Just yesterday I took it out for a drive and something new happened that I haven't experienced before... While driving it, the "headlamps not open" light came on but this time the headlights were only about 3/4 of the way open... But! If you flip the override switch down, they flip all the way open and the light goes out... If you flip the override switch back up, then the lights go back down to about 3/4 open... This is repeatable over and over. The lights still match up and are always in the same position as one another. And when you flip the override switch, they both open and close all the way and the light goes off when they are fully open. So obviously the limit switches and motors are still working good.

So my first instinct is that maybe the override/hold open switch needs cleaned or is going bad. Am I on the right track, or could it also be one of the relays causing this problem? I wanted to check here first before I tore into it, just in case anybody else has run into this. Thank you so much for any assistance! -Justin
 
Have you seen the simplified wiring diagram?
IF either upper limit switch is open AND your headlight switch is pulled the indicator light will be on.
In other words your Headlights have to be fully open for that light to be off.
Look there?
I'm not suspecting the override switch because it's function is to prevent the lights from closing.

https://www.forbbodiesonly.com/moparforum/threads/rotating-headlight-relay-modification.135356/

"headlamps not open" light came on but this time the headlights were only about 3/4 of the way open...
 
Last edited:
Have you seen the simplified wiring diagram?
IF either upper limit switch is open AND your headlight switch is pulled the indicator light will be on.
In other words your Headlights have to be fully open for that light to be off.
Look there?
I'm not suspecting the override switch because it's function is to prevent the lights from closing.

https://www.forbbodiesonly.com/moparforum/threads/rotating-headlight-relay-modification.135356/

"headlamps not open" light came on but this time the headlights were only about 3/4 of the way open...

Ok yes, I have the factory service manual that I used to fix it the last time with all the diagrams. I'm familiar with the "headlamps open" light going out when the upper limit switches get pushed in to tell the system that the lights are fully open.

So even though the lights will fully open and the "headlamps open" light goes out when you flip the override switch on (down) to keep the headlamps open, it could still be the limit switches?

Thank you again
 
Ok yes, I have the factory service manual that I used to fix it the last time with all the diagrams. I'm familiar with the "headlamps open" light going out when the upper limit switches get pushed in to tell the system that the lights are fully open.

So even though the lights will fully open and the "headlamps open" light goes out when you flip the override switch on (down) to keep the headlamps open, it could still be the limit switches?

Thank you again
Yes.
I typed it wrong though.
Those upper limit switchs are both closed until the respective headlight reaches full up to open it's switch taking away both grounds so your indicator light goes out.
 
Yes.
I typed it wrong though.
Those upper limit switchs are both closed until the respective headlight reaches full up to open it's switch taking away both grounds so your indicator light goes out.
Ok, I'm gonna take a look at it today. Thank you!
 
Sorry I was busy all day, finally a sunny day near 32 on a weekend.
I think you may need to check if the main control relay is energized or possibly the relay is bad as well.
With the original schematic it's actually possible to attempt to power the open and close feed to the motor simultaneously.
Not really the best design it would have been better to use a normally closed off the main control relay to power the open side relay.
You should be able to check power to the main relay when the light switch is pulled on.
If you remove the main control relay with the headlights closed and then pull the headlight switch and they open properly then it's either power to the main or the relay is bad.
Hope this helps.
 
I know that my override switch is "iffy" and they won't move till I flip it a few times. I believe one or some relays ground through that switch. That's how it prevents closing
 
I've had to review all this since I really hadn't noodled it out in years.
If he removes the control relay, I believe the headlights will still open but they will not close.
I think we need to clarify those "original schematics" if he is using them.
I don't think that FSM shows the internals of the relays and I'm not sure who drew the "simplified", but they are misleading.
(Unless noted otherwise, electrical diagrams typically show systems with the power off,)
I THINK they were originally found in the factory trouble shooting.
I've got copy somewhere.
However, the simplified diagram is showing the "opening" and "closing" relays as normally closed.
(Power off?)
But the opening and closing relays MUST be normally open contacts for this system to work as shown
However, the "control" relay IS normally closed.
This is because closing circuit MUST maintain closing power to close the headlights when the key is turned OFF.
That is the reason for the factory"control" relay AND the reason I had to add an isolation relay (AUX) in my modified system.
Once I removed the dependency on the parallel limit switch the system needed an extra relay to isolate it when the headlight switch is not in use .
Post 18
https://www.forbbodiesonly.com/moparforum/threads/rotating-headlight-relay-modification.135356/
His override switch may be flaky, but it's important to point out that it's function is to provide continuity to the "closing" limit switches.
If the override switch was stuck open ("OFF" position in the prints whatever that means) the "closing" relay would not be able to close it's contacts and therefore close the headlights.
 
Last edited:
I was having trouble with mine opening on their own, but they would open if I flipped the override switch. I noticed some charging issues, so I changed to a new solid state voltage regulator, and it solved my headlight problem also. Since things were working before that might be a possibility?
 
With a system that is over 50 years old low voltage can certainly cause problems.
I found that the motors themselves need more than 12 volts to reach anything approaching reliable function.
 
Hi again, thank you for all of the responses. I messed around with it for awhile yesterday. All of the limit switches tested good and are making contact when fully open or closed, the override switch tested good and I even tried another override switch with the same result. I also checked the power to the control relay which looks good. @Don Frelier, I did try what you recommended and pulled the main control relay out and with the control relay gone, the headlights would open all the way and the "headlamps not open" light would go out. When I checked voltage to the open and closed relays it seemed low. So it seems to be that control relay, I ordered a new set from topher so I'm hoping that cures the problem! :D
 
Excellent you didn't waste any time on that one.
:thumbsup:
Still mid-winter here so my stuff has to wait until warmer weather.
 
Hey guys, just wanted to let you know that the new relays did fix the problem. I got covid right after I bought them so I didn't get a chance to put them in until today. But as soon as I dropped them in, the headlights started working perfectly again! Thanks again for your help and knowledge!
 
Auto Transport Service
Back
Top