I had the lightening bolt signal happen two times. Once on a long steep downgrade, Loveland Pass, and the other time on I-70, downhill but not a steep section. Next oil change I mentioned what happened.
They said they did the reflash. A few days later on Loveland Pass at the same place it did it again. But it hasn't done it since.
Did the yellow symbol that looks like a engine also come on at the same time? It usually seems to take about three start stop cycles, turning the ignition off and restarting, to get the engine light to go off.