Sometimes you cant. Although, sometimes all you have to do is take the battery out and let it sit for a little bit. If that doesnt work then it probable is broken. If its water damaged but the phone and the battery seperatly in a bag of rice.
i don't now maybe just buying a NEW ONE
take it to the hospital.
if the screen is black you cant fix it is an internal crack that spread to the external part of the phone.
Call your provider and they send you a new phone just like that :)
If you get a black screen after installing mods, then it is a compatibility or incorrect install problem. If you get a black screen normally, force an update and this will probably fix it.
get a new phone
If the black marks are dead pixels then you have to replace the screen you cant fix it.
only if you have insurence. if you dont then no knew phone.
you can not
The following 4 ways can help you to repair your iPhone Stuck on Black Screen: 1.Fix iPhone Black Screen Problem with TunesKit iOS System Recovery Step 1, Connect iPhone to the computer Step 2, Download frimware package Step 3, Fix your iPhone 2,Fix iPhone Black Screen Problem by Hard Reboot 3,Restore iPhone to Factory Setting to Fix iPhone Black Screen 4,Seek for Apple Genius Bar to Fix iPhone Black Screen
Blue screen when playing online
You can fix Wii Black screen without sending it into Nintendo by pulling out the plugs at the back, and re inserting them.
Tell The Kid To Fix IT