Hey, sadly no lens cover, I cleaned the lens yesterday in the hopes that it was just dirty and I could definitely see into the lens. When I disconnect the camera from the RNS510 the screen stays black, perhaps it's got to do with using an RCD vs RNS, so really can't tell whether it's the camera or the unit, trying to work out a way I could test either. There are separate power inputs for the motor and the camera, but the two are wired in parallel on the wiring harness I got, so are both receiving 12V from the same fuse. I assume that these were wired correctly as the harness was from a car that had the RVC factory fitted. Thanks for your input though :)