You'll need an answer from someone who owns a 2009 Navigator, who found their code, otherwise you'll get guesses. When the DDM failed in my 2007 Town Car Designer, I was given all sorts of bad information. But I knew that in 2007 the key code was no longer visible on the DDM or anywhere in the vehicle. Maybe this was an across the board change for Lincoln/Ford? If it was, your DDM must be scanned for the code.