Chosen Solution
I changed lcd my s20 plus and also I replaced old original camera, but still didn’t work. If I clean the the cache memory and clean all setting from app>camera>storage>clean cache, then the all backs camera works. but when I switch front camera then it hang and still on blurry back camera. and then I open again camera app, only black display appear. and clean cache work back camera again.
Can you check the part number on the replacement camera part to see if is the same as the original part? In my experience, using a genuine Samsung part can still cause issues exactly as you’re describing(hanging when switching cameras/only showing black screen) unless it’s the same part number.Only the exact same part number replacement part will work for full functionality.
