Mercury remote keyless entry programming (sometimes called installation) and activation is a simple process. Actually, despite of the common name - remote programming, the process involves training the vehicle to recognize a new keyfob you purchased. This programming procedure should not take more then 1 minute if followed successfully. If it did not work or you missed a step, try programming your Mercury keyless entry unit again. You cannot brake anything.
MERCURY PROGRAMMING INSTRUCTIONS
Turn ignition from OFF to RUN (as far as you can go without cranking the engine) 8 times (one turn is from OFF to RUN and back to OFF) within 10 seconds, with the 8th time ending in RUN (8th time you only go from OFF to RUN and stop there) (do not start the engine). All doors will lock then unlock to confirm remote programming mode. Within 20 seconds, press any button on 1st transmitter. Door locks will cycle to confirm keyfob programming. Within 20 seconds, press any button on 2nd transmitter (up to 4 keyless entry units). Turn ignition to OFF. Locks will again cycle to indicate end of programming mode.
MERCURY REMOTE PROGRAMMING INSTRUCTIONS VIDEO BELOW