The key to our Challengers have a built-in transponder hidden inside. When a key is inserted into the ignition lock cylinder and turned, the car's computer sends a radio signal to the transponder. Unless the transponder replies with a valid code, the computer will not allow the engine to be started. Transponder keys have no battery; they are energized by the radio signal itself.

I found a video which demonstrates what happens if a key is inserted into the ignition cylinder without a transponder (i.e., same as hotwiring). Very interesting. See:

http://www.youtube.com/watch?v=bc1_VvbewDs

 

That's very interesting indeed. I wondered how that system worked.

 

that's pretty cool,but the Challenger doesn't have the same type of key.I'm guessing the fob has the transponder in it?and the guy could have used better lighting to make the video LOL