Need help programming keyless remote for 99 T&C

I have a 1999 Town & Country Lxi with 2 remotes programmed and working. I have a 3rd remote that needs to be programmed. Does anyone have instructions on how to do that?

Also, in a separate but somewhat related issue, when I unlock the doors with my keyless remote, the side-view mirrors occasionally reposition themselves so I have a nice view of the pavement. This van has the memory seat function, which works correctly when you press the buttons on the door, but does this weird 'mirror down' thing sometimes when the remote is used.

Any help you can provide would be great! Thanks.

I'll quote the '99 service manual here for you. Programming RKE (Remote Keyless Entry) Module
1) Using a functional key fob transmitter, unlock the vehicle and disarm the Vehicle Theft Security System VTSS
2) Insert ignition key into the ignition switch
3) Turn the ignition switch to RUN position without starting the engine.
4) Using a functional key fob transmitter, press and hold the UNLOCK button for a minimum four seconds (max. ten seconds).
5) While holding UNLOCK button, and before ten seconds passes, press and release the PANIC button. A single chime will sound to verify that the RKE module is set to receive the NEW Vehicle Access Code(s).
6) Within 30 seconds of the chime, press any button on each new key fob transmitter. After 30 seconds or when ignition switch is turned OFF, the RKE module will end the programming mode. A single chime will sound to verify that the RKE module will no longer receive additional Vehicle Acces Code(s).
7) When Vehicle Access Code(s) programming is complete, turn ignition switch to the OFF position and verify RKE system operation using each key fob.

Thanks for the instructions. I haven't been able to make it work yet, but I suspect the new remote may not be in working condition...

Any idea on the mirror problem? It's one of those strange intermittent issues, and I've not been able to find anything anywhere on the 'net that talks about this problem.

Thanks again!

The mirror problem has to do with how you programed your seat. You have to reprogram your seat and mirror at the same time. But, you can also program your seat mirror with your keyless entry too. It's so when you push the button the seat and mirror go to the position you like when driving. I think when you Program your memory seat, at within 10 to 30 seconds you can also program the setting to your remote. You hold the unlock button until you hear the beep. Try that.

Hi:
I had the same problem as you did. The service manual did not mention that the old one will erase to blank. Try to program all you remote one by one before turn OFF. I did program two Remote