Looks like it is just a factory cover if there is not an optional USB input. The wires are probably still run and that is why there is a harness in the back.
Unknown as to what that is. Like others have said there are wires behind it.
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Carl & Dawn
2015 Greyhawk 31FS (with 4x4 conversion by Ujoint Offroad)
2012 Lincoln MKZ Hybrid (our TOAD on a DEMCO Dolly)
DW, DSx2, DDx2 Catx2 Dog
Tampa Bay Area of FL