i think the S2k button is more of a gizmo than anything really.. but if u insist on finding some kind of "real function". it would be to restart your car when it stalls. so basically instead of turning your key again when it stalls, u just push the button. thats why s2k needs the key in and then push the button. looks cool but gizmo none the less.

 

What are your goals for this modification?

If you are trying to just get the car to start when you push the button then that should be pretty easy. Of course, you'll still have to insert the key in the ignition and turn it to the 'on' position, making this mod just for show. If this is how you hook it up the car will NOT shut off when you push the button again, unless you do some creative wiring (the car will shut off when you take the key out).

The M45 push button start is a fairly complicated system, as it has multiple antennas positioned around the car to detect a programmed key. I don't remember if the start switch itself had an antenna in it though. You would probably be best off using a meter to see if any two contacts are common when you push the button. Then, you can can use the push button to control a relay that will energize your starter wire. If you want to get the push button to work without putting the key in you can get a remote start system that has a (-) activation input. Of course you'll have to insert the key before you drive off.

Good luck and keep us posted on the progress!

 

I've driven my friend's Lotus Elise and you have to insert and turn the key, but then push the START button w/ your left hand. My friend's new E90 330i is similar, except you push the key into a slot. It's more of a pain than worth it.

 

I know this tread is kind of old but i did this to my BMW when i got bored one day, the 5 or 8 connections in the back do not matter, you will only need to use 2 or them, unless it lites up you will need 3.

Its fairly simple to put this in...you will need, a switch, a 30Amp/12Volt relay, and some wire, wire taps, and connectors.

on the relay there will be 5 connectors, the middle one should face horizontal and the top one will also be horizontal.

This image is off BMW diy site, this is what i used to help me put mine in, in my old BMW.



The Top connector and the left connector need to be jumped.

the left connector will attach to pin 1 on the switch

Now there are 2 wires that should be coming from the starter to the ignition
This is where i cant give precise details because i did this on a BMW and not a G35, but one wire was green, tap this wire, and connect it to the top connector on the relay this one has already been jumped to the left connector.

Now if you want to still be able to use the key, then tap the other wire, in my bimmer is was yellow/black, if you want it so u have to press the switch to start the car then cut this wire, and the side that goes to the started will be connected to the bottom connector of the relay.

on the switch, on the BMW i used a 4 pin switch and later a 2 pin switch, and it was the 4th pin on the switch, you must connect this to ground, so on your 5 pin or 8 pin switch one is the ground.

then once you are all together turn the key to the on position and hit the button.

Once the car is started you can hit the button all u want and nothing will happen, i hit it one time while driving and i thought it would be bad, but nothing happened, nothing at all.

hoped this helped a little

 

You should wire it so if the passenger touches it when driving it opens the sunroof and ejects the bastard...hee hee

 

LOL