Like brianl703 says, this system uses a resistor in the ignition switch, not the key. You will need to locate a manual that shows which two wires you need to tie into in the ignition harness to measure the Ohm value. Most DIY remote start kits have make/model specific instructions on how to tie in with a resistor, or bypass module which is basically a 'black-box' that allows you to dial-in a resistance value to defeat passlock. Bulldog.com used to give instructions right online.
G/luck
Joel