Completely Dead iPhone 6 repair tried lots and no joy

Completely Dead iPhone 6 repair tried lots and no joy Hi, I do small repairs on small devices but this is for MY IPHONE, embarrassing as I can't fix it to date. It just died one day..... and I mean its DEAD,
Asked by: Guest \| Views: 120

Total answers/comments: 2

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Guest [Entry]

"As you suspect, this is very likely a U2 problem. Depending on how experienced you are with this kind of repair, it is possible that you either have a defective replacement IC or it was not properly soldered with all pins connecting. If you applied too much heat, you may have shorted some solder balls underneath neighbouring chips or on the other side of the logic board. You may also have blown off some components.

Just ideas to check against...if you are experienced, you probably already verified this stuff, if not, then this is as good a time as any to learn :>).

U2 primarily functions as a communication chip. Tigris is responsible for generating PP_VCC_MAIN from either the battery or Lightning cable. The PMIC generates a multitude of power rails. Ideally, you need to test them all to ascertain full functionality."

Guest [Entry]

connect just the battery, press the power button and check pp_vcc_main, if you get the current. now remove the battery and connect just charging port and check if there is 5v but no pp_vcc_main. check L1401you.