When you removed your cover from the mount, it should have had the connection there to plug into. If so, did you have your battery switch on and 12 volt power to the rig? You can check the wiring to make sure it is hooked up by gently pulling it out of the opening. Maybe a wire is loose. Again, if you are on shore power or running on battery with the battery switch to on, you should have a blue light come on the camera. If it lights up blue, it should work.
Again, if you're prewired, pull the wires out and make sure they're still attached. Good luck and keep us posted.