This happened while driving a washboard road to go hiking. Stopped the car, went hiking. When I returned I started the car and all error messages were gone except Check Engine light. I drive home and noticed that the max regeneration button would not engage. I could run on electricity or gas and made it home. I charged the car then firmly checked that all fuses and relays were seated in the fuse box. I started the car and the check engine light went out. I have 850 miles when this happened, the car is running as normal the last day or two. Any ideas!