Oh God, you have not been on this forum in its hayday, have you?
@Ashtone ILL followed by any number is just an indication of where the illumination wheel is set to. That illumination wheel which is on the left side panel by the left knee. Turn it up and down, watch the display. Have to admit, first time it happened to me I got scared thinking YNANSB!!!
I believe the wheel is just sensitive to humidity, it mostly happens to me when it is raining or really foggy.
@KZJonny The info display flashes in two cases from what I recall: each hour of driving, and/or when ambient temp is around freezing. In later case I believe only temp readings flash though.