I have a 2014 C-Max SEL with about 47,150 miles on it. Until today it has performed flawlessly. We live in the Boise, ID. area and this year for spring break we decided to take our two kids to Tillamook, OR. We made the 500 mile drive yesterday and the C-Max purred the whole way. This afternoon, after spending a few hours at the ocean, we were going up a moderate grade when I noticed that I had to hold the accelerator down all the way to keep up with traffic going 45 mph. I looked down at the instruments and saw that the ICE was off and the electric motor was at max output. I had about enough time to think to myself "that's kind of odd" when "Stop Safely Now" popped up. I had to drive about a 1/2 mile to find a pullout. Once I was safely stopped, I shut off the ignition, waited about 5 minutes and pushed the start button. All electric functions resumed, but the ICE never started, (it didn't turn over, it didn't click...just a whole lot of nothing). Because I wasn't in the best of places to stop safely for a long period, I made a u-turn and drove about a 1/4 mile to a wider spot in the road. Once again I noticed that the electric drive was working fine, (it even showed that it was recharging when I coasted for a 100 yards), but the ICE remained dead. I called Road Side Assistance and they arraigned a tow to Tillamook Ford. Unfortunately the service department isn't open on Saturdays, but the dealership was kind enough to rent me their courtesy vehicle. I've been searching the forums for troubleshooting ideas, but haven't found anything that fits my symptoms. Any ideas would be welcome. Oh, just a few final notes. There's 3/4 of a tank of gas. All electric functions work normally. There are no trouble codes or warnings. I think the reason for the SSN message was that the hybrid battery was below 20% charge, (but can't confirm this idea).