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Headlight electrical problem

1K views 5 replies 4 participants last post by  Travis98146 
#1 ·
Hi, I am workign already days on a solution, but cannot find it.
68 coupe headlights problem.
All other lights work as they sould, rear lights, license plate, turn signal lights, brake lights, side markers front dash lights, all ok.
But, when I switch on the headlights, nothing is happening, except that the sidemarker lights start to burn brighter. Really strange. 2 days ago, the headlights were still kind of working. Left side was ok, right side was only burning very low. Yesterday I tried to search for errors in the cabling, did not disconnect anything yet. And all of a sudden, headlights did not wor at all anymore, no low beam, no high beam.

What I think is strange is that the side marker lights started to burn brighter. yes there is a dual bulb inside, but I thought that the 2 wires coming out of the side markers only have one 12 v wire and one ground wire. How is it possible then that the lights burn brighter, once I turn on the head lights??

The headlight switch is a new one...

I am desparate in finding the correct solution...

thx

Eric
 
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#2 ·
If you moved things around when you looked at the cabling, I suspect you have a loose or corroded connection somewhere. I'd start at the headlights and start wiggling cables with the lights turned on, working your way back to the switch. On my '66 the connector on the firewall where most of these wires go has been flaky.
 
#3 ·
Since you have the other front lights working, it does not look to be a bad ground. It could be a wiring or connector issue if they are in bad condition.

The first thing I would do is pull the connector off of each headlight and make sure the contacts on both sides are clean. Then check the connector contacts for power and ground with a meter.

I think you may have a problem with the the high beam switch on the floor. They can get very nasty if you have had a lot of rust in that area. You might pull it out and spray with WD-40 up under the foot cap and work the switch a bunch of times. And again clean the contacts on both sides.
 
#5 ·
So that would fall under the bad wiring heading. With all the other lights grounded there, and they all work, that ground point is doing its job. But you should take it apart and clean it up anyway and check all the other wires at that time. Glad you had an easy fix.
 
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