dice said:
So all I'm trying to do is try and figure out which wires I'm gonna need to connect the ignition relay and the engine start button to to get this thing to work properly.
OK, I'm not really sure why this switch uses two 12v switched inputs. I assume one is passed through to the starter circuit and the other is used for lighting the switch (perhaps)?
In any case, here is the break down on what you need to do. You need a switch that momentarily pulls pin 8 (green wire with black stripe) on the ignition switch (I18) to +12v. From that point, the ECM in the 4runner takes over to assure a successful start or graceful abort.
I'd say pin 2 (ground) on the button is fairly obvious. Pin 3 goes to pin 8 of I18. Pins 1 and 4 of the button go to a switched 12v lead. This circuit might need to supply upto 7.5A plus whatever the light in the button needs. You have two choices here. You can tap an existing circuit (maybe a bad idea), or you can extend the 30A AM2 fused circuit that feeds the oem ignition switch. Since AM2 is always powered, you will need to add a relay that is switched by one of your accessory 12v circuits. Since the relay only draws a few mAmps, that's a safe way to go about it.
I18 Pin 2 (Red)--Relay SW--Button Pins 1,4
Any +12v accessory lead--Relay Coil--GND
Button Pin 2--GND
Button Pin 3--I18 Pin 8 (G-B)
Depending on what kind of relay you use and which accessory line you tap, you might want to throw a 1000V 1A diode across the relay coil to shunt the reverse EMF generated by the relay coil when it collapses. Some automotive relays have this built in.
If you just want to wing it, you can forgo the relay and just tie pins 1,4 to an accessory line. There are MANY in the truck.
These are just my thoughts. I haven't done this and have no idea if it will work. You should assume that I am completely wrong and double check everything before you make any changes to your truck. In any event, I am not responsible for anything that happens to you or your truck.
Have fun!