Quality Aftermarket Ignition Switch

[DirtDonk]

OK, per your diagram the ACC-1 terminal should be for ignition and alternator and computer (if you have one) only.
ACC-2, as you said, is for everything else. So if you don’t have anything else you’re probably OK.
In other words, if you’re never going to be testing electrical stuff or listening to the radio, then there’s really not a problem.

 

[DirtDonk]

And even though I’ve never seen two prove out terminals, doesn’t mean there are not switches with that.
But they are strictly grounds, so make sure to never connect any positive power wires to those that don’t have a sufficient load elsewhere to keep it from shorting to ground.
If it needs a ground, then great. But if it’s already got a ground, you don’t want to short circuit to another one unless designed to do so.
On our vehicles, as you said, only the brake warning, light circuit has that function.
But not the brake switch.

 

[abn373]

I’ll try to double check some of those connectors on the back of the switch to see what they actually are. There should not be two prove out terminals. And there should be an on/run terminal only in addition to the ACC terminals.
The main thing I see wrong with your scenario is that with everything wired to the ACC terminal you have things like ignition and charging system running anytime you’re just listening to the radio. Or do you not have a radio?
There’s a reason they put those items on an ON/RUN-only terminal.

I do have a radio. You make a good point about everything being on the ACC2, I actually wasnt going to use that terminal at all, because I dont have heat/fan/def or any other options than a radio. I do have an electric fuel pump, but I have a dash mounted cut off switch for that. To be honest, with my old switch, if I was just listening to the radio with the engine off, which is rare, I would just switch off the fuel pump and the key would be in the ON/RUN position. I dont think I even realized that generic golf cart ignition switch turned to the left of OFF...I actually just pulled it out of junk box and sure enough it does. Now you have me thinking....havent wired it together yet.

 

[abn373]

And even though I’ve never seen two prove out terminals, doesn’t mean there are not switches with that.
But they are strictly grounds, so make sure to never connect any positive power wires to those that don’t have a sufficient load elsewhere to keep it from shorting to ground.
If it needs a ground, then great. But if it’s already got a ground, you don’t want to short circuit to another one unless designed to do so.
On our vehicles, as you said, only the brake warning, light circuit has that function.
But not the brake switch.

I wasn't sure why it had 2 prove outs either. On a few pictures of F-series, the harness had the wire removed from the pigtail on where the 2nd prove out would be, so must be some vehicle, I assume a Ford, that uses the 2nd one. Thats way over my level.
As always, I really appreciate the help and advice.

 

[Speedrdr]

Gonna chase a rabbit here and ask what a prove out is.

Randy

 

[Oldtimer]

Proves the brake warning light on dash is working. It creates a path to ground for warning light circuit, so that you know bulb is not burned out. I have never looked at warning light when starting my Bronco.

 

[Speedrdr]

Proves the brake warning light on dash is working. It creates a path to ground for warning light circuit, so that you know bulb is not burned out. I have never looked at warning light when starting my Bronco.

Much obliged, @Oldtimer. Never would have thought that.

Randy

 

[DirtDonk]

You’ll also sometimes see it written as “proof out“ as well as I believe one other term for it.
Slightly different words, same thing.

But it’s a very old concept for switches. I wonder if a brake warning circuit was its original function, or something else.
Never bothered to look up the definition.

 

[FordBronc]

Abn373.... so Airborne 3rd Squadron, 73rd Cavalry, with the 82nd by chance? I appreciate the wire walk and talk with pics. I am following close and if you want a OEM switch back side elec harness let me know.

Isn't leaving the key on a great way to burn up points, if you still have them? Or did you swap to Duarspark II?

 

[abn373]

Abn373.... so Airborne 3rd Squadron, 73rd Cavalry, with the 82nd by chance? I appreciate the wire walk and talk with pics. I am following close and if you want a OEM switch back side elec harness let me know.

Isn't leaving the key on a great way to burn up points, if you still have them? Or did you swap to Duarspark II?

Haha! well done! and very damn close, but I am a little bit more old school than that...you got the 82nd Airborne part correct, but when I was there it was 3rd battalion/ 73 armor regiment (airborne)....the M551a1 air droppable Sheridans....but you are correct, it's been reflagged as you described to Cav, which it always should have been because there were no tankers in the unit, it was all cav. Most people think it is just a combo of letters, but it was actually just me decades ago trying to think of a screen name for internet stuff that I could remember.

As far as the points burning up, that I can't answer, hopefully someone more knowledgeable can chime in. I switched to Pertronix back in 1999 and later switched to GM style HEI distributor in probably 2014. Both worked fine, although I think the HEI is a better set up. I am currently, while doing this ignition switch, also changing from Edelbrock carb/electric choke to Sniper EFI.....AND switched to a 1 wire 3G alternator...something tells me i should have done one at a time because I feel like a dog chasing 20 rabbits....and not catching any of them, but getting close to wrapping it all up and firing it up again since it has been sitting for almost a year and it's beach weather.

I reinstalled the dash today, so its a matter of putting it all back together and making a final decision on how to wire that ignition switch.

 

[FordBronc]

Thank you for your service, from one vet to another. Who just happens to be a 20 year regular Army Aviation guy. Cut my 1st year teeth on Huey's, Cobra's and 58's. I shared the wash rack with S-64 Sky Cranes (the NG still flew them). Then onto Blackhawks as a mech/crewchief and door gunner for 19 more years.

You should be good with the key on with the new stuff in there. I am watching the ignition wiring saga very close. Hang in there, you got this.

 

[DirtDonk]

No matter what type of ignition you have, it’s still just a good practice to get in the habit of.
Some ignitions are very resistant to overheating, while others, even electronic stuff, still suffer from that issue.
Keeping ignition duties on a dedicated circuit is the best practice.
Leaving the key off or in the ACC position guarantees you won’t have a problem.

 

[abn373]

No matter what type of ignition you have, it’s still just a good practice to get in the habit of.
Some ignitions are very resistant to overheating, while others, even electronic stuff, still suffer from that issue.
Keeping ignition duties on a dedicated circuit is the best practice.
Leaving the key off or in the ACC position guarantees you won’t have a problem.

I am not sure how to word this and not sound like I think this isn't an issue or that you are mistaken, because I highly value your opinion on all Bronco related tech. In my untrained mind, I see this ignition switch, and if we disregard the CRANK position and focus on RUN/ACC and ACC ONLY, it seems to me that 12v goes into the switch on the main terminal and depending on the switch position it goes to just the radio/heater/wipers (ACC) or goes to those plus the IGN systems, but it all passes through the same fuse panel that it does whether the engine is on or off, so it would seem that the IGN components would overheat or burn out by just being on while the engine is running because they don't get cooled by anything like the radiator or the fan..... I do not see the difference (as far as overheating the ignition system) because the only difference between the 3 switch positions is START/CRANK which I believe bypasses the fuse panel and goes right to the starter solenoid (and if you still have them the ballast resistor and such).

Paul, you are probably 100% correct, I just can't make the math work in my head and am always trying to learn.

 

[Oldtimer]

My guess is that it has to do with "duty cycle" of the circuits invloved.
When the engine is running the ignition system is cycling on and off, whether triggered by points or reluctor or crank/cam sensor. If engine is not running the connected ignition circuits are in a steady state, and cycling.

 

[abn373]

Finally got the ignition switch installed and wired. My "custom' dash is starting to look decent. As far as the switch, I didn't try and start the motor because I know it won't start right now because I am almost done with a Sniper EFI and I have the power to it disconnected. However, I did connect the battery and turn the key to ACC/RUN and things that were supposed to work did and when I turned the key off, the off part worked too...The crank part should be a no-brainer because that is a separate wire/circuit, so I think I have it wired all correct. I will follow up a bit more in a few days.

 

[302fix]

Nice upgrade. Following for the next time my dash comes out.
Same Centech setup...you had me at "Golf cart".

 

[abn373]

Nice upgrade. Following for the next time my dash comes out.
Same Centech setup...you had me at "Golf cart".

Thanks. Just an update, since I have the motor running now and have used the switch. It works flawlessly. Feels like a truck, not a golf cart and frankly it looks pretty good, unless you demand OEM look. And of course, the switch, being a common Ford part, its fairly reasonably available.
And it's nice to not have to look at the key to make sure it's facing the correct way to insert.

 

[gr8scott]

That is a nice upgrade. I've got the same Centch harness but never used the golf cart/lawn mower switch. Picked up the adapter for the stock switch.

 

[302fix]

What is the trick to getting the Key cylinder to sit down in the switch assembly?

 

[gr8scott]

What is the trick to getting the Key cylinder to sit down in the switch assembly?

From Jim at Wild Horses