new ignition lock cylinder

when replacing the ignition lock cylinder with a new ac delco unit, do i use the same key code or is it different now? I am unsure at how the car recognizes the correct resistance either in the computer or within the lock cylinder itself. someone help out?

The resistance is actually in the Theft Deterrent Mouled (TDM), you should be OK.. Ref shoebox http://shbox.com/1/pass_key.jpg