Yeap there is a cover as said above. Id do what circmad said and then give it a shot.
If you really want, you can actualy put a switch on the signal wires to the camera so when your driving along you can have it running too.
I can upload a diagram of how this is done.
But to actualy get to the wires is a real pain there beside the jack but theres a little metal cover thats in the way that you have to remove so that consists of undoing some of the plastic interior etc.