I managed to get this to work in my 2014 Ram 1500. Here's what I did.
1. Got in, closed all doors. NO key in ignition.
2. Buckled the driver's seat belt. Waited about 1 minute for all lights to go off that would.
3. Turned the ignition switch to the ON position and waited for the Seat Belt Warning Light to turn off.
4. Immediately unbuckled and then re-buckled the driver's seat belt 3 times within 10 seconds, ending with the seat belt buckled. I let it fully retract each time between unbuckle-rebuckle cycles.
5. Turned the ignition switch to the LOCK position but did not remove it from the ignition just yet. Wait, and a single chime sounded signifying that I had successfully completed the programming. Once I heard it, I then removed the key.
It's worth noting that the EVIC still displays a warning if a seat belt isn't bucked, but the chime never sounds.
Hope this helps.