I know both of my keys are in the house somewhere.. unfortunately I can only find one. I'm hoping the dog didn't eat the other. Does anyone have any knowledge of the interaction between the car and they key fob that activates the walk up unlock? I figured it was the car sending out a "ping" for the key fob to sent an unlock signal back and when the car heard the key fob reply to that "ping" it would unlock and present the door handles. I'm guessing the key fobs aren't programmed themselves, that the car is configured to only unlock for specific keys. therefor, I figure there is a way to get a key to send out the reply "i'm here" signal and use a very directional antenna to try to locate that signal. Hey, its a fun project, and worth trying for the $500 cost to replace a key.