Ignition Switch Wiring

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Aug 23, 2020 | 09:49 PM

Steve Harlow

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From: Sunshine Coast, BC

Ignition Switch Wiring

Quick question, I'm wiring my truck right now as 12 volt Neg earth, and I'm unsure about something regarding the ignition switch.

Got a repro one from DennisCarpenter, and it's rather unhelpfully labeled. It has three terminals, labeled "Coil" "Rad GA" "Am" and i'm unsure which of the latter two is battery/hot, and which is the accessories terminal, if there even is one. I'm also wondering if it has the usual off/accessories/ignition positions. It has three positions but with stuff this old you can never assume anything.

I want to say "Rad" stands for "Radio" and is therefore is the accessories terminal as the original doesn't appear to have that mark, only "GA". But I can't be sure.

I have the seized original with cut off pigtails, but all of the wires are yellow, which makes the wiring diagram useless. I would test it with my multimeter, but it went and died and i've yet to replace it.

Thanks.

Aug 24, 2020 | 07:58 AM

moejr

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From: Mendon, Massachusetts

The RAD post gets wired to the gauges metal connecting strap, AM gets wired to 30A circuit braker next to the instrument cluster & Ing. to the coil.

Aug 24, 2020 | 02:31 PM

Steve Harlow

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From: Sunshine Coast, BC

Quote:

Originally Posted by moejr

The RAD post gets wired to the gauges metal connecting strap, AM gets wired to 30A circuit braker next to the instrument cluster & Ing. to the coil.

So on a 12 volt negative earth setup, am i correct in presuming AM would be our power hot lead, and RAD would be the equivilant of the accessories lead?

Aug 24, 2020 | 02:55 PM

moejr

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From: Mendon, Massachusetts

Yes, I believe that's correct..... do a search on this forum for more info.

Aug 24, 2020 | 03:13 PM

Steve Harlow

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From: Sunshine Coast, BC

Quote:

Originally Posted by moejr

Yes, I believe that's correct..... do a search on this forum for more info.

I did and couldn't find much that was relevant, which is why i had to ask.

Thanks for the help

Aug 25, 2020 | 03:26 PM

jerryst

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This is the way I wired my 1955 ford f100 ignition switch. This is also a picture of wire from ez wire.
jerry

Oct 18, 2021 | 09:28 PM

yosemite98

Mountain Pass

Joined: Feb 2003

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Quote:

Originally Posted by Steve Harlow

Don't know if this helps, but here's my notes on how I wired mine. The diagram had Coil, BAT, GA, but my switch had IGN (Yellow), BAT(Red Green), STA(Black Green). So, GA = STA on mine. Can't recall what that was actually, nor what GA or STA mean. Mine is also 6 volt... with a positive ground. So, this may be useless.

Anyway, I came across this thread because my battery dies every once in a while randomly and I think there are 3 positions for the key and I randomly might be leaving it on the wrong one and draining the battery when I turn it off. Not sure what's pulling power even when I do that though, no lights are on.