iPhone 7 can't be turned on for repair because of water inflow

iPhone 7 can’t be turned on for repair because of water inflow

Machine model: iPhone 7
Malfunction:water damage no booting
Maintenance process: after PP-vdd-main Short circuit,The rosin smoke method and Short circuit are repaired,switch is normal and current change is also normal. But the screen doesn’t show. After careful observation, there is no display, not no backlight. Replace the display Short circuit chip directly.

iPhone 7 can’t be turned on for repair because of water inflow figure 1.

As you can see in the figure,corrode under the display chip is very serious. Clean and replace, but the result is still not displayed. See schematic showing VCC.

iPhone 7 can’t be turned on for repair because of water inflow figure 2.
It can be seen in schematic that if the display works normally, it will output 5.1V 6.0V 5.7V -5.7V VCC Connect the power supply startup measurement.

iPhone 7 can’t be turned on for repair because of water inflow figure 3.

PMU _ TO _ AOP _ Tristar _ Active _ Ready This reset signal is not only connected to the display chip, but also to the USB management chip, and connected to Connect the power supply source and CPU. It may be that water damage causes the original connected to this signal to burn out.

Directly disassemble the USB chip, connect the screen, boot up and normally display Stuck on Apple logo, but can’t get into the system. After replacing the USB chip, boot up and normally enter the system.Keep data succeeds.

iPhone 7 can’t be turned on for repair because of water inflow figure 4.

It has entered the system normally, and the prompt is being searched. It is estimated that there is still something wrong with Baseband. The customer only needs the information, and the Baseband will leave it alone. Just copy the information, and the repair is completed.