Tried this several times. Works in D, still locks up in R.
1. Get in vehicle and put your seat belt on before pushing the start button
2. Push the start button twice (to "Run"), but do not actually start the vehicle (keep your foot off the brake).
3. Once the Jeep is "on", you'll see the seat belt warning indicator on the display. It'll stay lit for a couple seconds. As soon as it turns off, quickly disconnect and reconnect the seat belt at least three separate times.
4. Turn of the Jeep.