If you search the forum, you'll find this is becoming a more and more common occurrence with the REC radios (which I am assuming you have).
When the radio screen is black can you change the input source, switch between AM/FM, or use any of the buttons along the bottom (right above the nav disc slot)?
If not, unfortunately, it is most likely time for a new radio. It's not the screen itself, but what most people think is a micro-fracture in one of the control boards, similar to what causes the red-ring of death on Xbox 360s. A few people have tried removing the screen and putting the PCB board into a toaster oven to re-flow the solder without any reports of success that I know of. Fewer and fewer repair shops touch these now, as they are becoming old technology and more trouble than they are worth.
Many just choose to go after market at this point or upgrade to a MyGig system. Replacement costs for the REC is $2000+ new, or ~$700 from a reputable e-bay seller for a used one with no guarantee in a couple of years you won't be in the same position.
Hi Doc,thanks for your knowledge but I wonder if you heard of replacing the board ? I saw on another forum of that being done,puchased for $90.00 online somewhere. Do you think that was a misleeding or false statement ?