This happened to me today, except I didn't get any type of system failure warning. My "engine to tire" indicator showing if the car is charging, using gas, etc just showed a tire and an engine, but no arrow / line pointing and the car was moving!
I was driving on the highway at 60
mph with my 2008 TCH from Kentucky, and all of a sudden it felt like I was slowing down. It was a gradual slow down, so I would be suprised if the engine completely shut off, but before I knew it I was going 40
mph and the gas pedal was not responding. Semi trucks were just barely missing me as it took a while to remember where the hazards were. Luckilly I came to my senses as I saw a bridge up ahead and quickly pulled over so the car wouldn't die on the bridge. I had about 6" of clearance from the cars and semis flying by and was freaking out so decided to start the car again, and it started!
Took it straight to the dealer and they could not find any error codes or repeat the problem during two 10 minutes test drives.
I did run over a deer (yes run over) a couple months ago which was $5000 worth of damage so was wondering if that could be the reason, but good (I guess) to see others have this problem.
I could have been ran over by a semi!