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My Civic 2007 Nav/audio screen is black. I know the radio functions but screen doesn't display - I can activate it with the talk button but not the ***** on the display panel. I can hear the Nav system click off when I don't recognize it by pushing non visible "ok" on display so I know that it exists as well. I have checked fuses - seem fine. I have pushed buttons to see if it was accidently disabled - no change. The cd opens so I removed and reinserted nav cd - no change.

Suggestions/advice welcome. I want to avoid service call if it is something easy to fix. Help + Thanks