On my 2015 Prius V5 the backup camera display does not appear on my screen when I go into Reverse, and I'm not sure it ever did. I have checked the video signal at the back of the radio/display (with my oscilloscope) and it is present so I am sure the camera is operating and the wires are good. I suspect that the command from a Reverse relay is not getting to the display to tell it to switch from Map or Radio over to Back-up camera. The blueprints I have indicate that this signal comes from a relay and fuse located in a mysterious box somewhere in the dash panel area and the signal goes to a connector on the back of the radio/display. Can anyone tell me where the relay/fuse box is and how to access it? How to remove the covering panels without breaking them and which connector and pins on the radio unit to test? My radio was replaced shortly after I bought the car in 2015 by the dealer. It has a navigation unit which works if I need it and a satellite radio. The Toyota blueprint system stinks. The prints cover foreign models and models with various configurations such as Right-hand drive and Left-hand drive. The hardware is not identified with conventional nomenclature such as connector numbers (P7 and J7). There is no explanation of 3 letter codes for the wires or enclosures. Bah. Humbug!
