Ignition switch and push button start

How-to's and repair secrets for your 4WD can be found here. Have a question? Ask it in here!
Post Reply
User avatar
HomeSkool
Top Notch Member
Posts: 130
Joined: Fri Jun 16, 2006 12:00 am
My tercel:: 87
Location: Nelson B.C

Ignition switch and push button start

Post by HomeSkool »

Hey everyone.
Long story short I've had an ignition failure and the key starting coil is toast and putting a new one is is'nt the best choice.
I am adding a toggle on switch, then a momentary push to start button. 8)

I've unplugged the plug that goes from the wiring of the car into the ignition switch in the key coil. No problem,
I've identified the markings to indicate what each (important) wire does, ACC, IG, ST, and them AM,

According to the Toyota manual the AM is the power supply, and the turning key simple allows power to flow to the ACC or IG or ST,
ACC I can only assume is accesory, IG must mean ignition, and ST is the starter.

I took apart the ignition switch but have had a difficult time figuring it out.
I really think it is as simple as putting the toggle switch in line with AM to IG for the "iginition on" switch,
Again the momentary "push to start" switch would be a button from AM to ST,

What I'm looking for is to get some feedback just to make sure I fully understand the wireing job I need to do.
If the AM is connected to the IG to "enable" the ignition IS it okay that that AM will also connect the "ST" to start the car at the same time?
I'm pretty sure that is how the switch works. But I don't want there to be power flowing into things that it was'nt ment to be.
But looking in the internals of the switch it looks like the switch sends power to all the places at the same time.

Also, I could not tell from the wireing diagram if this process simply supplys power to a relay or is the actual power that "starts" the car.
If there is no relay I better use heavy wires.

I'd love to hear from someone who has done this already. :)
Image
takza
Highest Ranking Member
Posts: 4414
Joined: Fri Apr 02, 2004 4:28 am
Location: Tibetan plateau

Re: Ignition switch and push button start

Post by takza »

You could just wire it using an 12V indicator light? You need current to the ignition/ECU...the toggle switch. Then you need momentary current to the starter solenoid...the button switch. You probably don't really need the ACC part of it...you could just wire this same as the ignition....meaning what usually runs when the key is in AC position will only run with your new ignit swtich on...but you won't be wanting to leave this switch on unless the car is running due to possibly burning out the ignitor. No running the radio if the car isn't running. Or you could add a separate ACC toggle switch if you wanted.
Give a boy a gun-give a biatch a cell phone-and pretty soon you almost got yourself a police state.

Orwell said: War is peace! Freedom is slavery. Ignorance is strength...

Image
User avatar
HomeSkool
Top Notch Member
Posts: 130
Joined: Fri Jun 16, 2006 12:00 am
My tercel:: 87
Location: Nelson B.C

Re: Ignition switch and push button start

Post by HomeSkool »

Thank you
That makes sence. I'll connect the acc and ignition to their own toggle switches.
As for the gauge of switch I'll use? It looks like a really heavy gauge. I can only assume there is no relay and the full current that starts the starter goes threw that push button. So I'll get some heavy duty switches. It did not look like there was a relay in line with this stuff.
Image
User avatar
ARCHINSTL
Goldie Forever
Posts: 6369
Joined: Sat Apr 30, 2005 1:52 pm
My tercel:: Goldie is a 1986 SR5 attualmente con Weber/also owned the first T4WD in STL in late '82
Location: Kirkwood, a 'burb of St. Louis

Re: Ignition switch and push button start

Post by ARCHINSTL »

HEED takza's caution about "but you won't be wanting to leave this switch on unless the car is running due to possibly burning out the ignitor."
Ask me how I know...http://www.tercel4wd.com/forums/viewtop ... istributor
Tom M.
T4WD augury?
"Oh, do not ask, 'What is it?' Let us go and make our visit."
T.S. Eliot - "The Love Song of J. Alfred Prufrock"
"Now and then we had a hope that, if we lived and were good, God would permit us to be pirates."
Mark Twain
takza
Highest Ranking Member
Posts: 4414
Joined: Fri Apr 02, 2004 4:28 am
Location: Tibetan plateau

Re: Ignition switch and push button start

Post by takza »

It all runs thru relays...so you'd just need regular duty switches? I'd use the kind that light up for the toggles...or you might leave them on...since you won't be removing a key. Problem is the ones they sell in the parts store have never lasted for me...meaning the lighted part of the switches. Maybe a separate indicator light that could be lit by either the ACC or RUN switches.
Give a boy a gun-give a biatch a cell phone-and pretty soon you almost got yourself a police state.

Orwell said: War is peace! Freedom is slavery. Ignorance is strength...

Image
Highlander
Top Notch Member
Posts: 413
Joined: Wed Mar 12, 2008 8:22 am
Location: Nederland, CO

Re: Ignition switch and push button start

Post by Highlander »

I'd suggest using a momentary contact for the start switch- did this in the race car with a momentary toggle rated at 5A 115/120V- It never failed-Probably the only thing that NEVER failed :wink: For the others I agree, a lighted rocker is probably best- though hard to hide.
'83 SR5-299K, -tRusty!
'85 SR5-265K--GOLD
'85 SR5-285K-- GOLD-New engine!
'85 SR5-238K -- Teal-Killed by a DD
'58 and '62 Austin-Healey Sprites
Post Reply