How to fix iPhone 8 Boot no Response
Turn on the power and the Apple logo will display normally. However, the phone is stuck on the Apple logo and cannot be fully activated. How should we fix it.
1:Connect the phone to your computer and restore it through iTunes. The SIM card is then inserted and the phone activated.
2:When returning to the function, the home button does not respond and the phone cannot be fully activated.
3:Remove the phone and disconnect the battery. Then remove the display.
4:Measure the power voltage of the Home Button.
5:Check the 3D flex cable of the display assembly for damage.
6:Remove the home button and check whether the flexible cable of the home button is damaged.
7:Replace the monitor components. Install the Home Button on the new display component. Attach the new display component to the logic board. Turn it on.
If the phone still fails to start properly, the fault is judged as the home button
8：Remove display parts. Switch to diode mode and measure the resistance between the J5800 pin and the ground. The J5800 has obvious repair traces under the microscope. Therefore, we can try to replace the connector J5800.
9：Remove the logic board and connect it to the PCB holder. Use high temperature tape to secure the connector next to the J5800.
10：Apply some BGA solder paste to the pad and remove the J5800 using a hot air gun.
11：Then solder with soldering iron and clean with PCB cleaner.
12：Apply some BGA solder paste to the pad. Align the new connector to the correct position. Then weld the new connector with a hot air gun
13：Assemble the logic board and connect the battery. Button the display panel and turn on the power. The mobile phone can normally access the activation interface.
14：Insert the SIM card and activate the phone. Home button response return function. But Touch ID failed。
15：Restore again through iTunes. When finished, activate the phone again. This touch ID is back to normal.
16：Use the phone's built-in bracket lock to remove the SIM card after the activation process.
17：Run functional tests. Trouble shooting.
Replacement for iPhone 8 lcd Screen
