Push button ignition

Peterjk · 09-26-2022, 04:43 PM

Hey everyone,
I'm looking to eliminate my 2005 Thomas standard key ignition and replace it w this push button ignition.
The Thmas key is nearly flat, so that would not prevent anyone from stealing the bus anyway, and I have other ways to prevent bus theft anyway.

Has anyone done this?
I dont know if the enclosed relay is needed, Im guessing the ignition already has one?
In theory, when I flip the Red switch On, that would like placing the ignition into Acc more, then just hit the button to engage the started .

Any help would be appreciated.

Peterjk · 09-26-2022, 05:24 PM

I found this conversation, maybe i can just wire the push buttom and bypass everything?

https://www.skoolie.net/forums/f49/i...tml#post471501

Truthseeker4449 · 09-26-2022, 06:05 PM

I've had one of these switches out in my bus, should have a 12v input, an output for ignition solenoid, an output to the starter solenoid, and maybe an accessory output that you don't really need. I can confirm it takes extremely little skill to hotwire the ignition or pick it with a rake. All the wires are hanging out in the open on the backside and the switch itself is only held on by the nut you see.

The relay is likely there so you're not passing the current through the switch/button itself or through thin wiring to it. I just had to deal with a bus at work where someone ran wiring directly to the starter and the wires melted out after someone held the button with the ignition off. Reran fresh wiring over 40 feet to the starter solenoid in the back of the bus and it works like a champ now.

So what I would do is wire the input to red toggle switch. Then tie the button input to the output of the switch, which still goes to the ignition output. I would pass outputs for each through a relay (which the input can again be tapped to provide switched power to the relays) to be on the safe side. The start procedure would be then to flip on the red switch, then push the start button.

Meathead · 09-26-2022, 06:10 PM

Yes. I did that. Instead of buying switches, I used the extra switches that I pulled out of my dashboard.

You need an on-off switch(ignition) and a momentary switch (start). I don’t have an Acc switch. My radio is now on the house batteries and I forget what the other accessories were.

So when you look at my dash you can’t tell which switches are the ones. They are next to each other tho. One is an emergency switch, the other was for lights.

I left the keyswitch, key in it, with a big ol key fob on it. Anybody who would try to start it will think the battery is dead.

The less keys the better! I have a keypad for the main door, so no keys at all.

[emoji3522]Dave

Peterjk · 09-26-2022, 08:17 PM

Thank you both, Im going to dig into this this weekend, Ill have more questions no doubt then, but at least now you've given me a better idea.

Peter

Peterjk · 09-27-2022, 03:35 PM

How do I pull out the ignition without making a mess of the dash?
Is it the torq's screws that hold all of it together ? Looks like 8 of them.

jimmythomas · 09-27-2022, 04:03 PM

Pull out the radio and you can see the wires. Unscrew the big nut around the key slot and push the switch assembly back into the dash, and then you can work on it thru the radio hole. Good Luck!

Peterjk · 09-27-2022, 04:22 PM

Well that was easy, thanks jimmythomas!

Too bad the ignition is way short to work with, geh. That's as far as it will come out.
Looks like 4 red wires and a tab on top with nothing connected. Bus starts w/o whatever was there.
I'm hesitant to pull off that plug from the end of the ign switch : )
I need to get in there to work w this not being any kind of a ignition expert.

Peterjk · 09-28-2022, 09:02 AM

I found a wiring diagram for this push button.
Then when i disconnect the plug from the ignition above, i will have to identify which wire is which. There are 4, all red. Anyone have a diagram for them?

Peterjk · 09-28-2022, 11:43 AM

I pulled the dash off to try to get a better visual of the ignition. Yep, its just 4 red wires, no other indication of which is which.

Peterjk · 09-28-2022, 12:02 PM

Took apart the ignition....here's the diagram i drew up.
Note: the GRD was not connected to anything.

So my plan is not to cut off the black plug, but to use spade connectors and plug them in there from the new push button switch.

Peterjk · 09-28-2022, 02:30 PM

What is ST ? Anyone?

Heres how I think I should to wire it, see if it makes sense.

Red Toggle ON : >>>>to>>>>Batt (on Ignition plug)
Red Toggle OFF:>>>>>>>>> Acc toggle on
Red Toggle OFF:>>>>>>>>>#3 on Start Button

Start button #4:>>>>>>>>IGN (on Ignition plug)
Start button #3:>>>>>>>>Red Toggle Off

Acc Toggle ON :>>>>>>>>>Red Toggle Off
Acc Toggle OFF:>>>>>>>>>ACC (on Ignition plug)

Unaccounted for is ST (on Ignition plug)
GRD (on Ignition plug) - had nothing plugged in origionally

jimmythomas · 09-28-2022, 02:43 PM

ST would be the solenoid terminal to the starter -- so this wire would attach to the output of the start button. Hopefully your new panel can handle the electrical current involved.

Peterjk · 09-28-2022, 02:50 PM

Aha, thanks for that.

So in my diagram above....Start button #4 would be split, one wire to IGN and one to ST ??

Start button #4:>>>>to>>>>IGN (on Ignition plug)
Start button #4:>>>>to>>>>ST (on Ignition plug)
Start button #3:>>>>to>>>>Red Toggle Off

I also forgot to mention there is a ground tab connected to the Red toggle, which will get grounded.

jimmythomas · 09-28-2022, 02:57 PM

I think you need some help with the wiring diagram.
As I see it, the red toggle "off" would get power from the "bat" wire.
Turning on this switch would send power to the push button, and the other toggle switches. The output of the push button would go to the "st" wire.
One of the toggles would output to the "acc" and the other to "ign".
What's wrong with the original switch?

Peterjk · 09-28-2022, 03:13 PM

I do need help [LOL], which is why Im asking, and thanks again for everyone kind reply's.

There is nothing wrong w the original ignition, I just want to eliminate it for a start button.

Here's the updated diagram. As I have one toggle switch [ACC Toggle], i would run 2 wires, one to the IGN and one to ACC.

Since I still have the original door interlock system in place, if I close the latch on the back window, the ignition is killed, so no one will be able to drive off anyway.

Possibly, the wiring on my ACC Toggle needs to be reversed, incoming power should go to the OFF side , then the wires to the Ignition ACC and IGN will come out of the ON side.

jimmythomas · 09-28-2022, 03:39 PM

That looks like it should work! You might want an inline fuse off of the "bat" terminal in case you have a wiring issue -- also it would be an additional anti-theft device if removed.

Peterjk · 09-28-2022, 04:56 PM

Awesome! ill test this out tomorrow probably. Ill post a follow up then w a cleaned up diagram.

Good point on the fuse, TY

Peterjk · 09-28-2022, 05:14 PM

Aw heck, i couldnt wait. Just tested it and it works like a charm!!!!

Everything can be killed by either turning off the Red switch or the Acc switch.
Thanks everyone! Ill post a updated diagram last to finish out this project.

AXett · 09-29-2022, 09:46 AM

Following this as I'm very interested in doing the same. My 08 International seems odd, curious if this is normal:

One click Left turn switches on the traditional "Accessory" solenoid (I believe). Allows things like lights and radio to work.

One click Right however does all the same, plus lights up the dash and runs the pneumatics and starts warming the plugs.

Is this just like the "Second click" (pre-ignition) position on a car switch? I've only got four wires coming out the back of my ignition switch.

I think if I go the button and switch route, I'll need two switches to represent the completed circuits in both the one left and one right positions, then the momentary for the actual turn over. Am I making this too complicated?

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