iPhone 13 cannot boot issue repair process sharing.
Defect Phenomenon
Purchased the iPhone 13 from a second-hand platform, but the phone cannot be booted normally. Not quite sure about the reason to cause no boot, maybe drop damage or water damage…
Troubleshooting
First, disassemble the phone and take out the motherboard to check, and find there are obvious water damage traces, the phone was water damaged.
Before starting to repair the motherboard, let’s tear off the black protective film and foams around the connectors, and keep them properly.
Then buckle the motherboard with the DC power supply and try to trigger to boot, the phone with abnormal large current and cannot be booted normally.
This means there’s component or chip is damaged.
Repair Process
Separate the motherboard
Place the motherboard on the heating platform, and heat the motherboard on the surface at the same time with a hot air gun to separate the two layers of the motherboard.
Tips: heat with a hot air gun and heating platform at the same time are faster and more efficient,
which could reduce the potential poor soldering risk caused by overheating.
After separation, we can see this arrow-marked area is seriously corrosive.
Then use the thermal imager to connect with the DC power supply to check, and find the damaged component.
Refer to the motherboard, it’s the arrow-marked capacitor that gets damaged
Since the small chips also get corrosive, to ensure the function stability after repairing. We should also resolder the two chips.
For the shorted capacitor we can just remove it directly.
Continue to resolder the two chips on the signal board. Clean the pads on the PCB with solder wick, reball the chip, and then solder it back with solder flux carefully.
Test with the DC power supply machine again, and the boot current is back to normal.
Then recombine the two layers of the motherboard with stencil and heating platform. After that, assemble the phone, put back the sticker and foams around the connectors, and test the functions, the phone can be booted normally and all the functions are also OK.
