Awesome Push Button Ignition





Introduction: Awesome Push Button Ignition

About: I'm working towards a Bachelors Degree in Mechanical Engineering. This year I'll be transferring to a university to finish the last two years of my degree. I've been accepted to the engineering program at Ca...

Here's a fun project that I did to my very first car. When I first got it I was quite happy with my purchase, but soon after that I found that I really wanted a sweet push button ignition and an engine kill switch, like a rocket or a race car or something cooler than an early nineties economy car. Well, it has been nearly a year and today i tore apart my dash, cut up some wires, soldered and drilled and figured and puzzled for about 5 hours and now, the final result, you will see in this instructable.
I'll show you how to wire in a push button ignition and an engine kill switch in your car. It's easy, as I have done all of the puzzling and figuring for you. It should take between one and two hours, depending on how fast you can take apart your dashboard, but could take considerably longer. This project cost me like 25 bucks for a soldering iron, wire, one relay, two momentary buttons, and a switch. If you have some of these it will be cheaper. Either way, this is a small price to pay for such a cool feature.

Step 1: Gather Materials

For this project you will need:

One Single Pole Double Throw Relay (a SPST normally open will work as well)
One Momentary switch, Normally open (toggle or button)
One Single Pole Single Throw Switch (toggle or button)

Soldering Equipment/Knowledge
Wire (I used 18 g)
Wire Cutter
Other various tools

Be sure that whatever momentary switch or button you get is a normally open, momentary switch.
anything else will not work for what we need.

Step 2: Open Up the Dash

Here you will need to get inside your dashboard to where your ignition harness is. This is near the keyhole. Once you get to this bundle of wires you will need to cut the Ignition Wire and the Starter wire, so also disconnect the battery first. You will have to find a wiring diagram for your car to know what wires do what. I can tell you that for Hondas the Ignition wire is black and yellow, and the Starter wire is black and white.
Cut these wires and strip the end enough that you can solder it or splice it well.

Just a caution, this step, more than any others so far, has a potential for really messing up your car. as long as you cut the wires such that you can splice or solder them back together you should be ok, but be aware that cutting wires to your ignition could become a problem.

Step 3: Assemble the Hardware

Now we will solder together the chain of switches and wires and buttons and relays to make this all work. This is by far the easiest step.
Basically the way this all works is that the Ignition wire, which needs to remain a closed circuit as long as the engine is going is connected to the relay, and we will borrow some of the current going through it to switch the relay and start the engine. Solder the wire ends to the Ignition wire or the starter wire as indicated.

Step 4: Put It All Under the Dash.

Now that your parts and wires are all wired in its time to test it. Turn the key to the "Engine On" position. Flip the switch on. Push the button. If you have wired everything all correctly you will start the engine. Now put your dash back together and put your buttons and switches wherever you like. You can drill holes in the dash and put the button and switch through there, or you can hide it under the dash.

Step 5: Show It Off to Your Friends

Alright! now you have a push button ignition in your car, just like all the high end sports cars, rocket ships, and computers. Go ahead and show it off, thats what you did it for, right? Be sure to post a picture here so we all can see it.



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    247 Discussions

    there a way to do a basic push button switch one to positive battery and one to starter it works but the battery overtime loses charge idk if the amperage of switch isnt enough or whats the problem.. my ignition took a crap.think the amperage on the push switch is a 20amp.

    1 reply

    Instead of hooking directly to the battery, try splicing into a wire that is only hot when the key is in the 'ON' position. Maybe this would help because it wouldn't be drawing a current all the time.

    You could also buy an adapter for your fuse box and run the wire from a fuse that's only on when key is on. This would give you a fuse for the wiring too which could be a little safer.

    okay so there is no need to do all of this... you basically need two 3 switches in total and you will not need the key to start only to unlock the steering wheel. you will cut out the ignition switch completely! Get 2 rocker switches with at least 30AMPS and one push button. Rewire the ignition wires to the switches. One switch will be to turn on ACC then, the other to go to IG1 and IG2. Then the push button will work as your starter! look at my youtube video below with the actually system at work.

    1 reply

    you should be able to just splice some wires into the ignition wires, so you can still use the key or the button to start the car. that way its still startable should something go awry with the new ignition system

    2 replies

    so do i connect the starter wire directly to one switch and the ignition to the other switch? then from the switch to the relay

    so what color wires from the ignition key go where on the relay?? still confused

    on the drawn figure wouldnt the momentary button wire be 86 and the one with the toggle be 30 and the and the looped 85 and the bottom right 87.

    Can you label which terminal is which in your "inside spst" and which terminal and which goes where? It seems like you have a fith terminal though but Its hard to tell.

    This is what I though

    Bosch usual relay - on fig 3 (inside spst relay)
    #30 bottom right
    #85 top left
    #86 Bottom Left
    #87 top right

    #87a Is not shown

    why relay? isnt there simplier way? Or maybe I dont understand something...

    2 replies

    The relay has a higher tollerance than the switch. and is less likely to fail. (if it fails your engine dies, loosing power steering and brake assistance. small car thats not a big deal but if you have an SUV or truck or are hauling your going to have a stoping adventure. lol

    Agreed. There are many relays in your car. Supporting those high amperage lines may be too much for a little switch to handle all the time.

    You should use solderless crimp connections in any auto application. especally wires. As the wires bounce the solder cracks and loosens. Crimp connecters have plenty of give. If one of thoes wires breaks loose. Should use an automotive relay as well. They just have stronger coils.

    do i need to use a One Single Pole Double Throw Relay... wat does it do

    1 reply

    It seperates the small switched for the possable 20amps the ignition can draw.

    in the wire drawing you didnt label a wire coming of the relay (button left) to what does it connect?

    Hall 9000 Can you please post a schetmatic for this project. PLEASE!!

    I have an interesting idea for a car engine. does anybody have any idea how you could modify a car engine to run off oxygen removed directly from he air around the car, basically making gasoline useless? I know it sounds too much like science fiction, but I think it could be possible. I have some idea of a design, but I don't have any solid ideas. any automotive engineers that could help me?