A special thanks to RVINSMCM for the info on how and where to look to fix our side camera. Sorry for the delay in posting this info, but this is what we did to make camera work. The camera was not the problem. The connection of the camera to the monitor was.
Hubby removed 6 screws from the panel that the monitor is sitting on and pulled the panel forward out if dash. He could see where the cable was not connected. Simple fix - push cable back into the socket and the camera worked. He pushed the panel back into dashboard and reconnected all 6 screws.
Once again, thanks for the heads up on this problem. Hope this info will help others who might be having same problem.