The constant power must be shut off. If your house batteries are off (switch is in store mode) that will cause it to loose its memory. Other than that check fuses. If all else fails pull the radio and check or run a new power wire. There should be two small flat metal bars in with your books that came with your RV that are for removing the radio. They just slip in on both sides of the radio. They will unlatch it and act as handles for you to pull the radio from the dash.
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