Yesterday at 5:30am when I started my 2015 FFH/43Kmiles, I saw all lights flash brilliantly - outside front, rear and cockpit screens. I thought I was seeing things because the car rolled out of the garage the same as always. After a 10 mile drive and sitting in the sun at 100 degrees, I started back home. The first 5 miles was unusual then the Nav screen said that the SD card was unreadable. I disengaged it and then pushed it in again and - no joy and no nav was available. I tried cycling the SD card installation again when I got home and was parked in the garage. No joy. I planned to take it in today. Prior to starting I took the SD card out but there was nothing out of the ordinary with the card. I reinstalled it and pushed the start button - surprise, the FFH did not give me any warnings. Nav was back and all displays were normal. I am loathe to ask a dealer to troubleshoot without a message. Anyone have a similar occurrence - momentary brilliant light followed by a SD card read issue later.