There is a PC board in the dash that controls the gauges, odometer, etc. If it fails, it can cause the symptoms you describe. There have been a number of prior threads about this problem. Happened to me while still under warranty. Speedo and tach froze at weird places, odo stopped working. I did a quick search too but couldn't find any of the prior threads. Maybe got lost when the board crashed. Good luck. Might be an expensive, dealer fix.