I have the procedure to enter the service function screen and I can take it out of demo mode (option set #1). But once I do that I lose the ability to travel and lift at the same time. Also, when in the service function screens, I can have it out of dealer mode and try to change option set #2 (hour meter start) and it will not allow me to scroll over to select the yes option. We have had the truck since it was new in 2003. It already has 20,000 some hours logged on the meter but it has stopped and no longer counts hours or miles. Could this be an issue with the display going bad?