I am having problems with my nav system. The screen goes blank and it says it is not connected or check connection....something like that. I have heard of problems with it before and that it usually is the start of a complete failure. I have checked my connections and I know that is not the problem it just says that on the screen. After a while it comes back and works perfect but sometimes it just will not boot up. Is this just the start of a complete failure? I am fearing it is. Any ideas?? Thanks