from the research I've done online, it seems like the motherboard or eprom (not sure what that is) is going bad in my unit. sometimes it works fine and others I have a black screen and the unit is unresponsive...

every now and then a bunch of Japanese characters will pop up and it will say "insert original cd" or something along those lines under the Japanese.

I've tried resetting it by pressing the auto and setup button at the same time and holding power for an extended period of time...eventually after rebooting the unit multiple times it will work but after the 3rd or 4th on/off cycle between driving to home and work the unit is dead again...

is my unit f*cked or is it salvageable? I've read that a burnt cd for NAV can cause problems over using a stock nav disc...TIA!!!