black screen

The map on my GV70 display unit goes black. The icon for the car shows in orange but otherwise, black. Any clues?

My backup camera is showing a black screen or occasionally horizontal gray lines briefly before going all black again. I took to dealer and they say it’s the harness. We checked continuity of harness at the trunk and all appears good. We tested for power at camera, but it was only for 6.7...