The LCD monitor in my old Lexus started to fade, particularly during daylight time. I can still see if the brightness is changed to maximum (I usually set at about 75%). On cloudy day, it works fine with 75% set up too. No problem when you use it at night. I am just wondering if you can replace the LCD with a new one, and how much will it cost? Are the spare-parts for the LCD screen still available and stocked, or do they still supply it?.
You just need a backlight bulb, not a new LCD.
I don't think replacing the CCFL backlight lamp in an LCD panel is a job for the faint of heart. You might be able to find a repair service that will do it for you if you remove the panel. Try 'googling' LCD backlight repair, and you'll find some monitor repair services.
To give you an idea of what is involved the following discussed lamp replacement in an LCD monitor, but once you get to the panel level, the Nav system LCD should be the same.
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