I have recenly brought my truck in for service and the type of work to be done meant that the battery had to be disconnected. When I got the vehicle back, I noticed that after 5-10 minutes the screen would start flickering then go haywire and finally turn blank. All the buttons still worked, but the display didn't. I also noticed the "battery" icon on the display come on about 20 seconds before it would start flickering and then would disappear. The unit would work fine after sitting for a while, like in the morning and when going back home from work. Does anyone know what the problem would be, how to fix it and where would I get the parts if need be?.... In distress....

Thanks