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Underdash harness resolution!!!


First, a big thank you to all that assisted me. Three years after my harness shorted out and needed to be replaced, it's done. (Fingers crossed).
I purchased a harness from Midlife 2 years ago. My back and hips have not been cooperating in allowing me to attempt it until now.
A couple weeks ago I decided to finally do it. As long as I rest and stretch every 15 - 20 minutes, my back has been fine.
At the same time, I decided to wire up the fog lights that have been waiting for their under dash harness for a few years also.
And, I had issues with trying to fire up the car after three years of sitting.
I read dozens of threads on the fog light install and watched a few videos and pored over multiple wiring diagrams. some contradicting each other.
The picture below shows 2 different wiring diagrams with 2 different sets of wires connected to the same 3 prong plug. (yellow).
My harness is a combination of those two diagrams. My 3 prong connector is also black, not yellow.
The left side diagram shows a solid black wire running to the fuse box. That is what mine is. The right diagrams shows a black/ red wire going to the fuse box.
The left side diagram shows a black/red wire going into the 3 prong. The right shows a green wire plugged in for the seat belt warning light which I have.
The fog light install requires you to plug in a 3 prong connector into your existing 3 prong black, yellow/white, black/red. My 3 prong is only 2 prong black, yellow/white.
I could not find any black/red wire anywhere that would plug into that connector. Ignore the one in picture #2, that is coming from the rear of the car.
So I plugged the 3 prong for the fogs into the corresponding 2 prong connector from the harness, Good, now where is that black/red. It is nowhere to be found.
My son stopped over and we traced everything one more time.
Well it seems that earlier in the week, I took the 2 black/red wires that pass through the firewall and taped them to the AC wires (no longer AV in the car) and shoved them over to the other sied of the dash. I could not see them because they come in too far up under the dash and I can't get in any position to look up that far.
So moving those wires over to the proper side of the dash, turning them sideways and plugging them into the 3 prong connectors for the fog lights and everything works as it should.
Unless my son came over and we went back to square one, and Midlife saying that the black/red has to be there, I wouldn't have found them
Didn't some site used to give out a D____S award for something like this? Blood was shed, Multiple hyphenated words were uttered. I caused my own headache.
Hopefully they'll be no issues when I put the instrument panel back in. Waiting on some bulbs.

Thanks again,


  • 2 Diagrams.jpg
    2 Diagrams.jpg
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  • Fog Lights 2.jpg
    Fog Lights 2.jpg
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Well-Known Member
Staff member
The differences you describe are the differences between the early and late 1966's, with the midpoint approximately March 15. Yes, it is confusing.
And congratulations for getting the car up and running and winning the old VMF Doofus Award!


The NorCal dude from Belgium
The differences you describe are the differences between the early and late 1966's, with the midpoint approximately March 15. Yes, it is confusing.
View attachment 34637

My friend had a simular problem with the alternator harness he ordered and had problems with charging the battery.

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