MAKING MY OWN PUSH-TO-START *HELP WANTED*

[Skeneypoo]

Hey everyone.

First DIY project on here. I'm making my own push-to-start button with a Normally Open Momentary Button.

I still have to order a few parts and likely break a few parts so there may be a bit of a delay between updates.. Anyways, let's get into it.

It should be noted that I'm by no means an electrician, but I do have a general understanding of how things work. Does that qualify me to do this? Absolutely not. But hell, life is an endless learning process..right?

Step 1: I purchased an OEM button to take apart and here's what I've discovered so far..

The physical button has 4 prongs on it (which I labeled 1, 2, 3, 4) when pressed, it closes the circuit between the middle and outer two connections (labeled A,B, C). So, yay, it's a normally open circuit.

I am not sure why they use 4 prongs on the button when the connection only requires 3..If you know, please let me know in the comments below.



Upon further examination, what I circled in blue says, "ANT1" & "ANT2" and it's connected, via the red lines, to those two prongs which has an inordinate amount of copper wire spun around the button housing. I assume those are used for the proximity sensor to the key remote.


All that being said, I'm thinking that the best course of action is to keep the OEM button installed, but relocated under the dash in case my remote dies and I need direct access to the proximity sensor.

I'd like to imagine that to use my own button in place of the OEM, I could just solder a 2 prong NO button between the connection (labeled A in photo 1) and the outer two connections (labeled B & C in photo 1) and call it a day.

I'll give it a try.

If any of you know more than I, please jump in and call me a dumbass followed with knowledge. I'd like to do this "the correct way".

-KS

[Skeneypoo]

Upon even further examination..you can see that the "push-to-start button" completes the grounded connection. The solder points circled in RED on the circuit board are the connections to the row of 5 pins on the connector (top left). Whereas the solder point circled in BLUE, labeled GND) shoots straight through to the other side of the housing, also circled in BLUE (top left).


Because of this, I feel that splicing a Normally Open button, as shown below, into the stock wiring connector should work as an additional "push-to-start" button to turn on the ignition and start the car.


I always thought using a switch on a grounding connection was sketchy. Apparently not.

Once again, if you believe my thoughts are flawed, please let me know.

Side note: That's not the button I plan on using.

[mabviper]

I would use a DPST switch rather than an SPST switch. You can see that from the white piece where 1-2 is completely isolated from 3-4.

Sent from my Pixel XL using Tapatalk

[DustinS]

Are you trying to mimic the factory set-up? or just use the factory button as the starter trigger?

[Skeneypoo]

Originally Posted by mabviper

I would use a DPST switch rather than an SPST switch. You can see that from the white piece where 1-2 is completely isolated from 3-4

I appreciate it! I just did a little research on what all the different Double and Single throw and I seem to understand. Basically a DPST is just one toggle that control 2 separate switches. Makes sense.

I don't disagree, just trying to get to the bottom of it haha, so I could be wrong, usually am..but when looking at the photo, it seems like on the black piece the strike pad labeled A is contacted by the white piece first.

Since the 2-3 prongs, on the white piece, make contact with strike pad A, on the black piece, before prongs 1-4 make the connection, I'm pretty sure that when 1-4 eventually touch, ABC + 1234 are all connected in one circuit.

So if anything, i'm thinking a SPDT would be the switch to go with.

[Skeneypoo]

Originally Posted by DustinS

Are you trying to mimic the factory set-up? or just use the factory button as the starter trigger?

Not sure if I understand your question, but I believe i'm just using the factory button as the start trigger..

Using this pic as a reference. When you're in your car and press the "Start-Stop" button, all it's doing is pushing the white piece forward so that the prongs (1,2,3,4) make contact with (A,B,C). So instead of using the white piece to make the connection, I want to use my own button to make that connection. So the OEM button will still be 100 percent functional, somewhere accessible under the dash, but I could also use a separate button to start and stop the car

[DustinS]

The button is just that. A button. All the tricks to make the car start and go into accessory mode and such are controlled behind the scenes by a separate module.

Have you looked at the Wiring Diagram? Assuming your BRZ is using the keyless entry and push button start already. Starts at 60 and ends on 78:

BRZwiringi.pdf

If the car uses a key, Advanced Keys sells a product to mimic the smart entry/start system. Unless all you want to do is add a button to start the car like a race car. Which means just adding a button to add power to the starter relay.

[all4spl]

Originally Posted by DustinS

The button is just that. A button. All the tricks to make the car start and go into accessory mode and such are controlled behind the scenes by a separate module.

Have you looked at the Wiring Diagram? Assuming your BRZ is using the keyless entry and push button start already. Starts at 60 and ends on 78:

BRZwiringi.pdf

If the car uses a key, Advanced Keys sells a product to mimic the smart entry/start system. Unless all you want to do is add a button to start the car like a race car. Which means just adding a button to add power to the starter relay.

How do you get rid of the key with the advanced key kit?

[DustinS]

Push Button Start...

^ That Thread should be the one with the install.

[Skeneypoo]

Originally Posted by mabviper

I would use a DPST switch rather than an SPST switch. You can see that from the white piece where 1-2 is completely isolated from 3-4.

Sent from my Pixel XL using Tapatalk

Nevermind, you're completely right. Thanks!

[Skeneypoo]

Originally Posted by DustinS

The button is just that. A button. All the tricks to make the car start and go into accessory mode and such are controlled behind the scenes by a separate module.

Have you looked at the Wiring Diagram? Assuming your BRZ is using the keyless entry and push button start already. Starts at 60 and ends on 78:

BRZwiringi.pdf

If the car uses a key, Advanced Keys sells a product to mimic the smart entry/start system. Unless all you want to do is add a button to start the car like a race car. Which means just adding a button to add power to the starter relay.

My BRZ uses the keyless entry and push button start already. I'm just trying to swap out the OEM button with a custom one. I've checked out the diagram quite a few times. When you say "All the tricks to make the car start and go into accessory mode and such are controlled behind the scenes by a separate module" All of that happens within the OEM push-start button assembly. Not necessarily in a completely different module.

[Skeneypoo]

I'm becoming quite the artist..ha

So this is my theory. When the OEM button is not pressed, strikepads A, B, & C are all independent from each other, but when you press the button, A, B, & C are connected simultaneously.

So, by splicing the 3 wires from the connector to my own DPDT momentary button, it should work in the same way. When not pressed A, B & C are separate from each other & when pressed, they're all connected.

Using a DPST button makes more sense, but for the button i want to use, i couldn't find it in that configuration. Once I get this all dialed and tested I'll make a video on the install. Should be pretty simple.

[Skeneypoo]

Originally Posted by all4spl

How do you get rid of the key with the advanced key kit?

With their kit, I believe you have to continue using a key. Unless you wanted to get sketch and craft..maybe you could wire up a toggle switch to emulate the key turn..who knows.

[DustinS]

Originally Posted by Skeneypoo

With their kit, I believe you have to continue using a key. Unless you wanted to get sketch and craft..maybe you could wire up a toggle switch to emulate the key turn..who knows.

Nope. You can either get a dummy key made or cut the spare and turn it to the on position to get rid of steering lock. or remove steering lock altogether (which is in the thread). unplug the ignition plug on the column as you are using the advanced keys stuff to control that.