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Fog light switch wiring 1966


I am trying to wire up the under dash harness for the fog lights to the switch.
I have watched several videos and read numerous threads, but I still haven't found what I'm looking for. (Now I'm singing in my head).

I just replaced my harness with one from Midlife. It has the blue/black wire (#477) with the ring connector on it so I think I'm good there.
CJ Pony Parts videos shows them attaching a single black wire into the black bullet connector from the headlight switch. I don't have one.
The harness I have, has 2, 3 prong connectors that are supposed to connect to a 3-prong connector from the headlight switch. (Photo two). I don't have that.
What I do have, is a 2-prong connector with a 1 black and 1 yellow wire. (Photo one).

I believe that I can eliminate their blue/black wire from the circuit breaker and hook the BATT side up to wire #477 that has the ring connector on it and is hot all the time.
The plug for the switch and the plug to the firewall are obvious.

So the question is, is the 2-prong black and yellow wire connectors from the headlight switch the proper place to hook up the 3-prong connector from the harness so my taillights go on with the fog lights?
If so, what is the third wire on the connector on the harness for? (red/black).

Thanks for all the help.



  • headlight black yellow.jpg
    headlight black yellow.jpg
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  • Fog Lights.jpg
    Fog Lights.jpg
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Well-Known Member
Staff member
Black and yellow/white wire are the running lights and fuel line connectors that go to the tail-light. It and the backup lamp wire (single bullet) will plug into one side of that 2 pin connector and acts as a pigtail between the two 2 pin connectors. The third pin is simply your backup lamp single wire (black/red). That's how the foglamp system taps into the running lights.