Quality Aftermarket Ignition Switch

[302fix]

Thanks! I figured it out shortly after posting. Knew that little hole has something to do with it.

 

[302fix]

Just an update. I think I have the wiring figured out. I was going to use the pigtail harness I got (73-76 F100) but the quality did not seem that great and the wires seemed a gauge or two smaller than my Centech harness. Also, the plug doesn't really lock in like a modern harness with a clip and such, so I am 90% sure I am just going to use 4 spade connectors with shrink wrap and it will be a better more waterproof seal anyway. and will pull out just as easily as the F100 plug (which sucks because I want it locked in to prevent it from pulling out. I may still figure that part out. Anyway, after sorting through a million blurry diagrams and wrong model year pictures online, I just decided to use multimeter and do continuity test on the terminals and I should have just started there. If any of my electrical terms are incorrect, I won't be insulted if you correct me. I am an amateur and try to remember the terms I have heard along the way from others.

I made this simple diagram of the actual back of the switch. For me it is only 4 wires and to be honest it is only really 3, let me explain, the ACC2 position (what I call turning key to the left of OFF) should only probably have the heater circuit it on it. I have completely deleted everything related to the heater/fan system in my truck. The whole circuit does not exist nor does the hardware, but that is where you would wire it. Instead, I have the ACC2 circuit and the ACC1/RUN (what I call the first notch over between OFF and START) both wired into the same circuits on fuse panel, which is fine for me, but maybe not you (aftermarket self-made fuse panel) so for my simple truck, everything works on both key positions.

There are 2 terminals that I believe are called PROVE OUT, I am not using these because I do not have a Brake Warning Light or Brake Switch. I believe (someone chime in if I am incorrect) that this is where you attach those items. Apparently, some Fords (mustangs) used 2 terminals, and some used 1. I don't know personally.

I have a 1990s Centech harness, so for my diagram I used the color of wire for the arrows/words associated with that spade terminal if that helps anyone. As far as an OEM harness, I don't know the color wires you would have. I will update more when I get a little farther along.

View attachment 898105

From the Centech wiring harness I have wired like this
Color Centech FMC
Purple ST Start (purple above)
Red BAT Battery (red above)
Black Brake warn Black Brake Warn Prove 2 (green above)
Black ACC ?? Would guess ACC1 (white above)
White IGN ??


I'm sure the Black Centech wire went to ACC and the White to Ign but that doesn't align with above.
Can anyone help me out with the unlabeled Black and White wires from the Centec kit?

 

[DirtDonk]

Unlabeled? No writings along their length?
Maybe I missed something. I’d better go back and read it again.

 

[302fix]

Pealed it back. Black is marked ACC. White is IGN.
Based in this pic I'm not sure where IGN would go.
https://classicbroncos.com/forums/attachments/ign-jpg.898105/

 

[DirtDonk]

Is that an ignition switch from their kit? It’s not a bronco switch.
Unless it’s a 78 or 79 model that is.

 

[toddz69]

Is that an ignition switch from their kit? It’s not a bronco switch.
Unless it’s a 78 or 79 model that is.

Which one are you referring to? If you're referring to the one pictured in post #35, that's a switch used in F-Series trucks from (I think) '67-'79 and '78-'79 Broncos. See also post #5.

Todd Z.

 

[DirtDonk]

I had forgotten that. There’s a link in post number 44 that shows the backside of the switch.
Given the one you just mentioned, that makes total sense.
And explains the two prove out connections.

 

[302fix]

Got it all sorted.
This is an F-Series '67-'79 and '78-'79 Broncos Ignition switch upgrade from the Centech (golf cart) switch.

From the picture in post 19 (https://classicbroncos.com/forums/attachments/ign-jpg.898105/).
Purple start from Centech to Purple start in picture.
White IGN form Centech to White ACC1 in picture.
Black ACC from Centech to Orange ACC2 in picture.
Red BAT from Centech to Red Battery+ in picture.
Brake Warn from Centech to green Prove.

Key position testing info
https://www.ford-trucks.com/forums/attachment.php?attachmentid=136443&stc=1&d=1454874853

Thanks all!