How to program your 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, and 2006 Mercury Grand Marquis remote keyless entry fob alarm by yourself at home without going to the dealer.

Turn the ignition from OFF to RUN 4 times within 3 seconds, with the 4th time ending in RUN.
All doors will lock then unlock to confirm programming mode.
Within 3 seconds, press any button on 1st remote transmitter. Door locks will cycle to confirm programming.
Within 3 seconds, press any button on 2nd transmitter (up to 4 transmitters total possible).
Turn the ignition OFF. Locks will again cycle to indicate end of programming mode.