Hey guys ok i have been fighting some electrical issues. Had no dash illumination lights which was solved by installing a new headlight switch. Now with the switch pulled out my headlights intermittently shut off. I cant figure out if its a bad switch or what. The plunger was a pain to get back out for some reason. I am also trying to diagnose a driver side marker light that isnt working, both inner and outer, bulbs are good … on the outer one i am getting power on both sides of the socket which i think isnt supposed to be happening ??
Headlight issue
- Thread starter Baker7888
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It takes a fine touch to get light switch perfection ... they can be tricky even when you try the right things.
Press the release button and remove the center stalk with knob completely. Unscrew the face ring and lower the switch out of the dash. Temporarily replace the face ring onto the switch. Now push the release button a few times then hold it down all the way. Insert the center stalk all the way in before releasing the button.
If the center stalk seems to get caught, turn it slightly back and forth while continuing to insert it fully. If you get it inserted fully then release the button and test your lights operation with the switch visible and in your hand. Confirm that the spade lug terminals and wires are fully seated and not loose at the wire or at the switch.
When you get everything working, then use a Sharpie to make marks on the center stalk. When you re-install the switch into the dash panel you can use the marks to confirm full insertion. Hopefully you can get it working. Otherwise try removing some of the bulbs while testing to eliminate any shorting or bypassing through the filaments. I hope we are talking about incandescent bulbs all around!
Press the release button and remove the center stalk with knob completely. Unscrew the face ring and lower the switch out of the dash. Temporarily replace the face ring onto the switch. Now push the release button a few times then hold it down all the way. Insert the center stalk all the way in before releasing the button.
If the center stalk seems to get caught, turn it slightly back and forth while continuing to insert it fully. If you get it inserted fully then release the button and test your lights operation with the switch visible and in your hand. Confirm that the spade lug terminals and wires are fully seated and not loose at the wire or at the switch.
When you get everything working, then use a Sharpie to make marks on the center stalk. When you re-install the switch into the dash panel you can use the marks to confirm full insertion. Hopefully you can get it working. Otherwise try removing some of the bulbs while testing to eliminate any shorting or bypassing through the filaments. I hope we are talking about incandescent bulbs all around!
Hey John thanks for the response. Yes incandescent all the way around. The switch is brand new. It will work like a charm then the lights just go out after a few minutes …. Then they come back seemingly on their own. I will say that some of the bulb sockets are pretty crusty, including the marker lights, the front driver side ones dont work. Wondering if this is related? One of the sockets has power on both sides i think this is an issue, no?
Bad dimmer switch. Also a good time to think about upgrading headlights. Lots of good choices for not a crazy amount of money. Original system marginal at best
Dimmer switch as in the entire plunger unit? Its brand new. Not that i’d be entirely surprised…but is there a way to test? Can i jump two of the wires for headlights?
Here's something that you really should have to help with this & any other electrical issue.
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Agreed, lol. I did not expect there to be all these wiring issues. Oh well. Diagrams should be here in a few days. Thanks for the link.Here's something that you really should have to help with this & any other electrical issue.
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It's time to get methodical with your voltmeter. Hook up the light switch out of the dash panel so you can access each terminal and wire. Make a drawing of the wires coming out of the switch using the 2 PDF diagrams I downloaded from Chilton. Use the diagram colors to label each wire on your headlight switch.
In general terms the 12 volts enters the switch, goes through the switch, and comes out of the switch. Then it goes along that colored wire, through fuses (maybe) and to each bulb socket. Then it goes through the bulb filament and to a ground return.
For the first quick test set up your voltmeter to monitor the voltage on the headlight output wire at the switch. You can use a 12 volt testlight or small bulb instead of a voltmeter.
When the headlights go out (by themselves) check for 12 volts coming out from the switch. Voltage means the switch is getting power and feeding it toward the headlights. But no voltage means the switch is becoming open, or the main power feed into the swich is disappearing.
This type of testing works for the taillight circuit or the instrument lamps circuit too. Once you know the headlight switch is working you can move your tester out to each socket.
Beware ... sometimes an open or poor ground at one of the sockets will allow a small amount of curent to back feed into another socket. A voltmeter will show that as a voltage, but a test light will be a more accurate test.
Be methodical, draw any kind of diagram to keep track. You will get there.
In general terms the 12 volts enters the switch, goes through the switch, and comes out of the switch. Then it goes along that colored wire, through fuses (maybe) and to each bulb socket. Then it goes through the bulb filament and to a ground return.
For the first quick test set up your voltmeter to monitor the voltage on the headlight output wire at the switch. You can use a 12 volt testlight or small bulb instead of a voltmeter.
When the headlights go out (by themselves) check for 12 volts coming out from the switch. Voltage means the switch is getting power and feeding it toward the headlights. But no voltage means the switch is becoming open, or the main power feed into the swich is disappearing.
This type of testing works for the taillight circuit or the instrument lamps circuit too. Once you know the headlight switch is working you can move your tester out to each socket.
Beware ... sometimes an open or poor ground at one of the sockets will allow a small amount of curent to back feed into another socket. A voltmeter will show that as a voltage, but a test light will be a more accurate test.
Be methodical, draw any kind of diagram to keep track. You will get there.
Thanks for the diagrams John. I will take a look at this again hopefully tomorrow. My two sockets are in questionable condition so i ordered new ones.
I also didnt exactly realize this at first but my dimmer switch/directional switch lever is busted off. I bought the car like this last year, backed it off the trailer and into the garage and pulled the motor and trans so it was kind of an oversight till now and i have no real backstory on it other than it seemed to be all original.
As far as the headlights go, I jumped from power to headlight terminal on the switch connector and lights work fine although i did not sit there for too long to see if they go out. Somehow I think i got a bad replacement switch.
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