My 2010 navigation system goes offline very time I get onto a freeway. I cannot use the radio or my bluetooth. I went to the dealer and they told me it would cost $150 just to try and find a problem and not sure how much more it would cost. Then someone said that he has seen frequent issues where the satellite sends the system to another state all together. It turns out my unit was set to New York and not California. It was ok for a day then it went wacky again. Has anyone had this type of trouble?
That's very odd ($150 to diagnose?!?! holy crap!). Perhaps try another dealer who's willing to see what the problem is without charging an arm and a leg OR try disconnecting the 12V battery to reset (you'll lose the radio presets and will have to recalibrate the auto-up/down power windows but that's easy to do). Wait a few minutes before plugging the 12V battery back again and see if that resets the GPS receiver.
While you are disconnecting the 12V to effect a system reset, check your battery voltage. I know all sorts of electronic gremlins would come out to play in the Gen II when battery voltage and capacity were low.
I had a similar issue, I wound up getting a new Nav DVD there were software updates on it and that fixed my issues.
