Tail light/brake light harness plug in.

[CURSED GEARS]

Greetings.
Been rebuilding my truck for the last few years and have been working on the wiring harnesses.
I've used the search function and read a lot of threads pertaining to the tail light wiring harness, but no specific info on what I need.
Here is my question. The plug in to the wiring harness on the inside of the cab, that runs through the firewall, what's it look like? I assume it matches up to the intermediate wire that runs down the channel of the frame. Does the inside connector, (plug) attach to the main inside harness under the dash?
I took this harness out a couple of years ago and can't remember. I have been working on my harness cleaning it up, repairing wires, and such, but can't find the inside plug that goes in the firewall any where. I seem to remember a smaller wiring harness detaching from the main harness when I was taking it out of the cab and wonder if that could be it?
Anyway. If you guys let me know or a picture would be helpful, I would appreciate it.

Cursed Gears

[CURSED GEARS]

Nobody?

[ray_mcavoy]

What year truck?

If it's a 62-66 or 67-72, the intermediate harness should have a molded rubber connector that fits into a hole in the firewall and also serves as a grommet. The dash harness should have a 3 or 4 wire (depending on the year) connector that plugs directly into the intermediate harness right where it goes into the firewall.

[CURSED GEARS]

Its a 70. I'm missing the female plug that goes through firewall, and of course the wiring. does that section plug into the existing harness under the dash? When I google it, all I can find is stuff about the intermediate wire, and the actual wiring harness that plugs into the tail lights. Can't figure out what I did with it. Tore up the garage today with no luck.
And thanks for the response by the way

[VetteVet]

Originally Posted by CURSED GEARS

Its a 70. I'm missing the female plug that goes through firewall, and of course the wiring. does that section plug into the existing harness under the dash? When I google it, all I can find is stuff about the intermediate wire, and the actual wiring harness that plugs into the tail lights. Can't figure out what I did with it. Tore up the garage today with no luck.
And thanks for the response by the way

The harness that plugs into the firewall just above the distributor has The tail light (brown), backup (light green), right turn/stoplight (dark green), left turn/stoplight (yellow) wires in it.

The turn brake light wires inside the cab in the harness run to the steering column connector up to the turn signal switch.

The brown wire for the tail lights runs to the headlight switch.

The light green wire for the backup lights runs to the back light switch which is part of the neutral start switch on the steering column.

I'm not sure if there is a separate harness for just these wires or if they are part of the cab harness with a jump off plug to mate with the firewall harness.

This diagram shows the plugin and the wires going to the steering column connector . The brown wire goes to the headlight switch (not shown) and the light green wire goes to the backup light switch. Ignore the arrows they are for the accessory wire to the fuse panel.

[CURSED GEARS]

Thanks for the responses guys. I'm good now. It should work fine when I put it back together, It was working when I took it apart a million years ago.

[ray_mcavoy]

You're welcome!

The intermediate harness should have ends that looks like this:


(photo borrowed from Classicparts.com site)

One of those ends goes into the hole in the firewall. The dash harness should have a somewhat-rectangular shaped 4-wire female plug that fits directly into that end of the intermediate harness. Wire colors on that plug should be brown, yellow, light & dark green.

[CURSED GEARS]

Your picture didn't come through, but I know what the intermediate wire looks like, I, should, I got to sets! One came with my other bed.
Rectangular huh? Ill take another look, but I already checked the connecters for those color combinations. I'll have another look. Thanks again for your help.

[CURSED GEARS]

That's weird, the picture shows up now.

[El Dorado Jim]

I would think it is part of the dash/ in the cab harness....then the intermediate harness plugs into that..

[CURSED GEARS]

Thanks, I found it. I typed it up so you folks would know, but I guess I forgot to hit send. I was looking for a round fixture, not a rectangular one. Then, the wire colors were painted concealing their identity. Thanks for the response.

[Fredthecat]

Where can I obtain the firewall male/female connectors and new wire terminals for 1964 C10 taillight intermediate harness?? Not the entire harness (available), building new one.

How do terminals remove from original rubber connectors?

Fredthecat

[ray_mcavoy]

Originally Posted by Fredthecat

How do terminals remove from original rubber connectors?

The terminals are non-removable. They are permanently molded into the rubber connectors.

Originally Posted by Fredthecat

Where can I obtain the firewall male/female connectors and new wire terminals for 1964 C10 taillight intermediate harness?? Not the entire harness (available), building new one.

The non-sealed version of these connectors are plastic with snap-in terminals. They're Packard/Delphi 56-series and are available through several sources such as www.terminalsandconnectors.com, www.waytekwire.com, and www.mouser.com, just to name a few.

Unless you absolutely have to make your own harness (due to custom length, etc.) it would probably be best to simply purchase one of the readily available pre-made harnesses with the molded-on rubber connectors. The only other option for making your own would be to salvage some good used connectors with several inches of good wire on them and splice the wires.

[Fredthecat]

Thank you very much. This is what I expected. Got the old terminals out...by pulling , but the wire insulation stayed in the plug.

Yep, looks like I'll bite and buy a harness. then modify it.

Thank you
FTC