Headlight Switch Terminals

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Just picked one up. I was getting ohms through everywhere but the headlights. I just wanted to make sure it was the headlight terminal. Will see if that fixes the problem in the morning...

 
Ohhhhhhmmmmmmm. A Buddhist chant. Doesn't seem to work on headlight switches...

 
Okay... So I put in the new switch today. Nothing. I wasn't 100% that it was the culprit to begin with but I figured with the state of corrosion the old one was in it was an inexpensive start. The fuses are okay. The parking lights work. Just not the headlights. I've tested the headlights too, hooking them up directly to the battery.

I was going to start scrapping off insulation and checking for current next in the engine bay. I was also going to check the back side of the fuse box but I'm not sure why since everything else on that circuit is working. Is there an in line fuse anywhere for just the headlight wiring? Any other suggestion short of replacing all the headlight wiring?

Thanks!

 
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Just got done looking at the wiring diagram on the forum for a '73. So that answered a lot of questions about inline fuses or relays. I didn't see a single on. My next train of thought was this: The pigtails for the headlights are now reading the same voltage as what is going to the parking lights. Could this perhaps be an amperage issue. I have all the original wiring but have much newer headlights. The backs have a stamp that read somewhere in the early '00's. My theory is though that the lights should still come on but just not be that bright.

 
Just got done looking at the wiring diagram on the forum for a '73. So that answered a lot of questions about inline fuses or relays. I didn't see a single on. My next train of thought was this: The pigtails for the headlights are now reading the same voltage as what is going to the parking lights. Could this perhaps be an amperage issue. I have all the original wiring but have much newer headlights. The backs have a stamp that read somewhere in the early '00's. My theory is though that the lights should still come on but just not be that bright.
Just throwing this out, have you checked to make sure that the connector has not fallen off the dimmer switch? Might want to cycle that a couple of times too. Also you should have 2 grounds, one on each side of the apron by the lights, make sure they are grounded. properly.

 
Thanks. That was the direction of my thoughts when I was thinking about new bulbs in an old system. If I can atleast get these guys to come on I'll add that to the list. Glad you showed me this one because I was looking at a couple of other sites and they wanted double $$$.

 
I'm running that exact system and have had it on the car 3-4 years. I have no complaints. I actually thought about using a second set of lights/fog lights lower in the grill and using a second harness tripped by the other headlight switch to operate them.

 
Nice. Definitely going to pick up that harness.

So I checked the grounds and they are hooked up. I even removed the bolt and touch the terminal around. I disconnected the dimmer switch and the center terminal has 12V.

So next step in the solution is to replace the dimmer switch?


Here is the ground on my passenger side. I am looking at the right wire?

2v29vgj.jpg


 
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Nice. Definitely going to pick up that harness.

So I checked the grounds and they are hooked up. I even removed the bolt and touch the terminal around. I disconnected the dimmer switch and the center terminal has 12V.

So next step in the solution is to replace the dimmer switch?


Here is the ground on my passenger side. I am looking at the right wire?

2v29vgj.jpg
The red-yellow wire is the power coming into the dimmer switch. Locate that pin (blade) on the switch. Then take a meter and put one lead on the pin on the switch where the red - yellow wire would connect to and the other lead to one of the other 2 pins on the switch. one of them should show continuity. Then depress the switch once and the other pin will now have continuity if the switch is working.

If this works the switch is good and your issue is some where else, makes sense?

 
Thanks. Makes perfect sense. It's the same process I did on the leads of the headlights and the headlight switch. I picked up a new dimmer switch on my way to work just in case. I'll test the blades this weekend. If there was continuity and/or the new switch doesn't work... Thoughts on where to go next since I am getting 12 volts at the dimmer switch? After the dimmer switch it looks like a straight shot to the headlights themselves on the wiring diagram.

 
Thanks. Makes perfect sense. It's the same process I did on the leads of the headlights and the headlight switch. I picked up a new dimmer switch on my way to work just in case. I'll test the blades this weekend. If there was continuity and/or the new switch doesn't work... Thoughts on where to go next since I am getting 12 volts at the dimmer switch? After the dimmer switch it looks like a straight shot to the headlights themselves on the wiring diagram.
I'll check to see if there are any other connectors between the dimmer and lights.

Since you got the new dimmer switch just connect the harness to the new one and see if the lights come on. A quick and easy check.

 
No other connections or splices of the high and low beam wires between the dimmer switch connector and the two headlight connectors.

Corrosion at either the dimmer switch connector or the left hand headlight connector can give you these symptoms. The signals first go to the driver's side headlight connector and then over to the passenger side.

 
Thanks. Since there's nothing else between the two that was going to be my next step. If the new dimmer switch doesn't work I'm going to make a couple of pigtails for the headlights. Hopefully the switch works. If not the pigtails. Since I'm getting juice at the dimmer switch connector I'm going to rule that out. My next phase would be to replace the wire running up to the driver's side first. At least start back at the firewall and move to the grill looking for where the juice stops flowing.

 
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