Chosen Solution
Recently I replaced the rear case lens by taking the camera out. After putting everything back together the camera worked fine for a minute or so then after closing and reopening the app it shows a black screen,front camera works though and when switching from the front to rear a blurred image of the front camera is displayed instead of the black screeen. The flash works though! Does anyone know the solution,is it something related to the logic board? Thanks in advance
Try replugging the rear camera ribbon cable, make sure to unplug the battery prior to doing so.
Disconnect the camera and reconnect see if it helps flash and camera are two different parts on the 5s. That’s why flash still works.