Chosen Solution
My iPhone was working perfectly, I don’t use it much, I turn it off and leave it for days or months without touching it. The last time I used it was 1 month ago. Yesterday I wanted to turn it on but it was dead, BLACK SCREEN, when I plugged it to a charger and put its back close to my Ear, I could hear a sizzling sound (sssszzz ssszzz). I tried to charge it for several hours but in vain. I couldn’t see anything (the cable drawing, or apple logo or anything, only a black screen). I tried the Power button+volume button method to hard reset it but it didn’t work.
Fairly sure it’s a short circuit chip problem. A reputable repair store that does micro-soldering / board repairs for iPhones can fix that for you.
