Vehicle lost power with no prior warning at highway speeds. Vehicle then displayed ‘Stop Safely Vehicle will shut off soon’ message. In order to attempt a reset, driver must turn off, leave vehicle with FOB and secure vehicle. Then return to vehcile and start up in an attempt to reboot. Check engine light remained, but functioned nromally for a day. Vehicle did the same on another freeway at 70 mph, and continued with the same events above several times, some producing immediate repeat message, or other times getting a half mile down the road. Depending on availability of a shoulder or center divide, this is extremly dangerous to fail unexpectedly on the highway. In California there are freeways with over 6 lanes, try getting across 6 lanes of traffic with no power, in limp mode. Vehicle is now at dealer awaiting diagnosis and repair. I continued with the vehicle when the tow truck service via Chrysler corporate stated 60 -90 min response. My saftey was more of a concern if I had to wait that long.