I have been trying to fix my backup camera for some time now. I bought my 2012 E350 with 97k on it and had the problem since the time off purchase. When I put the car in reverse it doesn't show the lines of anything. Just tells me to check my surroundings and shows a black screen kind of like a tv when you disconnect the HDMI cable. I've tried wiggling the connections and replacing the fuses. Could there be an actual problem with the camera itself?

 

Fuse f84 (7.5A) @ rear SAM (trunk). Definitive diagnose pull fault codes, DIY without codes check harness/connections inclusive of trunk hinge & power supply module if all are fine replace camera part # 2128202797 see attachment.