If you need a new remote, you need to go to the dealer. If you have a remote that isn't working, replace the battery; stand next to your truck and push both "lock" and "unlock" buttons simultaneously until you hear the door locks cycle (about 4 seconds).
Your remote might need replaced, the buttons are probably worn out. They usually don't last for 10 years!
the dealer does it with a scan tool
On the inside of the keyless entry remote or sometimes on the back it explains how to do this. I believe you hold the unlock button along with the lock button for 7 seconds near the car. It will explain it on the inside of the keyless entry remote.
It can have power locks with out keyless.
Take the remote apart and it says to push the buttons once each or twice each try this
The location of the remote keyless entry module on a 1998 Saturn is in the rear of the passenger compartment. It is underneath the trim at about shoulder height by the right rear seat.
Try turning the ignition on and off about 10 times until the door locks, lock and unlock, then lock with the remote done.
My 98 Ram sport does it is a control module behind the dash if your does not and can be installed quick at the dealer .
First unlock and open the hatch, the horn alarm is now disarmed and you can unlock the driver side door.
It should , my 1995 Explorer XLT has a keyless entry pad on the drivers door and came with 2 remotes
My understanding is that you need to have it done at the dealer. There is no way of "cloning" an existing remote onto a second OEM one without dealer tools.
In a 1998 Ford Explorer : The RAP module ( Remote Anti-theft Personality module ) is used with your anti-theft system and your keyless remotes ( each vehicle with keyless entry has it's own factory code )