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Front marker light issue

A4x4Junky

Sr. Member
Joined
Jan 9, 2007
Messages
550
Loc.
South Jersey
I pull the headlight switch out to the first click. All 4 lights work. Pull the headlight switch on to the second click (headlights on) and the rear lights stay on, but the front marker lights go out.
Headlights do work, but Im confused as to what would cause the front marker lights to go out ... any thoughts on where I could start looking? Hate to unwrap more harnesses than necessary.

Thanks,
Anthony
 
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A4x4Junky

A4x4Junky

Sr. Member
Joined
Jan 9, 2007
Messages
550
Loc.
South Jersey
A weak ground, most likely. Test voltage from the GROUND wire of the non-functional lights to the battery (-) post. If it's more than 2V, repair the ground circuit.

Sounds good to me. Thanks for the help. I wasnt even sure where to start the search.

Anthony
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
37,070
What year?

That is normal operation up until about '70.
It is carry over from the days of low output generators. Back when generators only put out 15-30 amps you didn't have much current to play with. Since headlights mark the front of the vehicle the park lights are turned off to save what little precious current there was. Federal regs changed and required the park lights to stay on about '70, By then generators were gone and alternators were standard and could handle the power without problem
 
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A4x4Junky

A4x4Junky

Sr. Member
Joined
Jan 9, 2007
Messages
550
Loc.
South Jersey
What year?

That is normal operation up until about '70.
It is carry over from the days of low output generators. Back when generators only put out 15-30 amps you didn't have much current to play with. Since headlights mark the front of the vehicle the park lights are turned off to save what little precious current there was. Federal regs changed and required the park lights to stay on about '70, By then generators were gone and alternators were standard and could handle the power without problem

This is on a 67. So, possibly normal.
Knowing that might save HOURS of tracing wiring... ;)

Thanks for the heads up...of course now I could look at the option of wiring them in the same as the rear...though I guess that isnt necessary. Hrm.

Thanks,
Anthony
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
37,070
For a '67 that is correct operation.

If you want the lights to stay on there are a couple of ways to do it. easist is to add a jumper between the front and rear light outputs on the headlight switch. Others will pull the wire out of the front position and add it into the rears.

Personally I would leave it. I think it is part of the charactor of the early years. Part of the reason I want a '67 U14 for my next project.
 
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A4x4Junky

A4x4Junky

Sr. Member
Joined
Jan 9, 2007
Messages
550
Loc.
South Jersey
For a '67 that is correct operation.

If you want the lights to stay on there are a couple of ways to do it. easist is to add a jumper between the front and rear light outputs on the headlight switch. Others will pull the wire out of the front position and add it into the rears.

Personally I would leave it. I think it is part of the charactor of the early years. Part of the reason I want a '67 U14 for my next project.

After thinking about it, I agree. If this is the way it is supposed to be I will leave it.

Thanks again for the help. :)


Anthony
 

.94 OR

Contributor
Bronco Guru
Joined
Jul 5, 2009
Messages
2,209
Loc.
Willamette Valley, OR
When I rebuilt my '71, I used a '67 body. I had to integrate wiring harnesses from both years to match up with the holes in the '67 firewall. There were things I liked from both, but I didn't like the lack of a corner marker if a headlight went out. Since the '67 did not have fender lights it got real dark if the main headlight went out and I drove it enough in the dark that I wanted the markers. I also wired in my electric wipers when I rewired it as well.
 
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