So i was driving down 35E, doing about 74mph (or thats what my normal speedometer said) so i put it into diagnostic mode, then into my digital speedometer, and it said i was doing 83. This is a good thing because before this, i was kind of dissappointed in my cars top end acceleration, but now i've found out the error, i am happier with the car. Its neat to know that the only error is high speeds (above 70 mph on normal speedometer) otherwise the 2 speedometers show the same speed. And is the digital one the accurate speedometer, i always thought digital speedos were more accurate because of the lack of gears and stuff from the transmissions.