How to program the 2002 Nissan Sentra remote keyless entry:
Sit in the driver’s seat and then close all of the doors. Push the “Lock” button twice on the driver’s side door panel. Insert the key straight into the ignition, and then remove it six times within 10 seconds. Do not turn it each time.
Insert the key again. Turn it to “Acc.” Push the “lock” and “unlock” buttons at the same time on the remote. Remove the key from the dash ignition. Push the “Unlock” button on the door. The remote is programmed. Test it. If it doesn’t work, repeat the programming process, paying careful attention to the speed at which you push the buttons and insert then remove the key.