Had to unexpectedly go out of town, so haven't been able to continue this thread until today.
Removed the camera and it's lead. The connector, camera and wiring show no signs of wear, moisture or corrosion. The connector (between the camera and the wiring to the cab) is quite small and it appears deep inside each is a 4-prong (like, real tiny) setup (male/female). The connection was/is tight.
To be sure, I cleaned off each connector, re-connected and put the truck in reverse. Same "Video Signal not Detected" message.
On the camera side is a single wire running from the camera to the connector, while on the vehicle side is a two wire set-up (red and black). This wire runs into the cab where it is plugged into a fuse box on the firewall. There is a wiring harness that then leads to the head unit. All wiring/fuses appear ok throughout the system. The camera picks up power through the box (not cut into the reverse light at the tail end).
If the 4-prong setup at the connector is any indication, the wiring in the camera end will be minuscule and a pain to cut into and splice farther up-stream to confirm if the camera is the culprit, so any suggestion on how to determine the condition of the camera without doing that would be appreciated.
As this system is no longer available, the only replacement I have found so far has completely different connectors and I am not sure of the compatibility to the head unit. And as there is a few hundred dollar cost, I would like to confirm exactly what/where the problem is before I go that route.
Marv