You might want to get one of these
It allows you to "map" up to 4 different cables from end to end. Place the colored cap on one end, and connect the control to the other. Whichever cable the control is connected to will be shown by the appropriate led lighting up next to the color dot.
Larry, Eileen, and Finley
2004 Alpine 36FDDS
Third motor home, first Alpine, no need for another.