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Fastest Way to Solve iPhone 7 Plus Won't Turn On Problem

Received an iPhone 7 Plus with reboot failure, the owner wants us to fix it. The original problem with this iPhone 7 Plus is that the iPhone touch screen shows half bright half black after the boot, when repaired this problem, the iPhone 7 Plus won't turn on.

Repair process

After we received the iPhone 7 Plus, first of all, we need to use JM-P01 Essential Toolkit to disassemble the iPhone, remove the iPhone motherboard and then put observe it under the VGA Camera 7-45X TrinocularStereo Microscope, there has traces of water, and many small original components have been torn down.


Connect iPhone motherboard to the computer with C48 MFI USB Cable, there is no response. With the help of YH898D hot airgun and tweezers, we remove the iPhone NAND Flash, and then connect it to computer again, still no response.

Use Fluke 15B+ DigitalMultimeter to measure the booting power supply and I2C bus, the data is normal. Now we start checking the disconnected iPhone NAND flash that without connecting to the computer. Remove USB tube U4001, measure the resistance of the substrate, we found the E4#(PMU-AOP-TRISTAR-ACTIVE-READY) is short circuit.

Open the WUXINJIDongle to check the iPhone schematic diagram; We can know that this point is connected to the CPU display IC U3703 C2#. So we remove the U3703, and then measure the C2# and U4001 E4# again, the short circuit fault has been resolved.


Reinstalling the iPhoneNAND Flash and U4001, and replace a good U3703, after finish these, assemble the iPhone to test, the iPhone 7 Plus turned on smoothly, the fault was solved.
 


Read more professional cell phone repair solutions please on www.vipfixphone.com


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