Rear cameras failed on my Symbol

Over a 2 week period first the tailgate then the distance camera images went blank on the display screen. Picture failure was preceded by a red screen with Chinese/Japanese letters. Can anyone help me solve/repair this problem please? David

Well obviously the screen seems ok, the 'lettering' on the screen probably says something like 'loss of signal' or 'no camera detected or similar.

That leaves the camera itself, 12v supply to it, the earth from it, or the camera to monitor wire, the supply USUALLY comes from the reverse-light circuit, are the reverse-lights working??