Connect your Receiver to the cable inside the RV... turn on the power.. Test the each connection at the docking station... their should be 12 volt power flowing through the satellite connection.
An easy way to check... if you have a "Satellite Finder" meter.... when connected to the proper cable and when the Receiver is turned on... the meter should give you a light or a sound....
The Receiver sends 12 volt power to the LNB which is on the dish.
Good Luck !
Marv