I Have a Prius 2007 and the gps/navigation system wont power on,(Black screen) Nothing No Power. I have tried a few thing but nothing. The strange thing is that two(2) times it came on and all buttons/reverse cam everything was working. But It only stayed on for a few minutes.And Both times it came I was putting the car in reverse. I tried to duplicate that many times but nothing. I was wondering if anybody might have had a similar problem. I would appreciate any help or suggestions someone maybe could give me.Thanks you very much. Sean.