3 
4 Replaced front, back & battery. Buzzes twice and no display.
iPhone 4s - The phone was pretty messed up; the front was dirty, really cracked, and missing pieces of glass at the top. The back was all cracked. I was told the battery was dead (plugged it in - wouldn't turn on).
We went ahead and replaced the front, and power button (it wasn't clicking - button had gone bad).
From the BACK WE COULD SEE LIGHT BUT THE FRONT DISPLAY WAS BLANK.
A few seconds later it started BUZZING TWICE every 5 or so seconds.
We replaced the battery - there was no change.
Because the front got so dirty I'm guessing the motherboard is damaged? Maybe?
The water indicator on the charging port is red and I've been told the top left side of the logic board is getting warm... Ideas anyone?
42 
Thanks con but the screen is for sure good (tested it on another phone).
Could it be the logic boards connectors to the screen are bad?
Like I said, the top of the screen was dirty and big pieces of glass were missing.
If that IS the problem, can I do anything to save the logic board?
--
Could it be anything OTHER than the screen??
EVERYTHING I read says "something's wrong with the screen connection" :-/
由 ali 完成的
CONCLUSION: they sold it on ebay, haha!
由 ali 完成的