Promblems with odomitor ERROR

Well I noticed about a week ago that my main odomitor says Error instead of my miles. On the odomitor last time i noticed it was at about 200,000 miles. But i always put my odomitor prefixed on the trip odmitor. I dont know why but if anyone has any knowledge of this please let me know, thanks.

If there is a button on the side pertaining to E/M (KM/Miles), try pushing it and see if you get the right mileage number showing this time.