Solutions for iPhone 6P no display no backlight problems

While we got the iPhone 6P, the emails describes it can't work normal, doesn't display and no backlight.

Though we found there no obviously damage outside,  it still don't like a new one. Its master said the iPhone 6P  was repaired once, so we decided to disassemble it and found the faults.

Use phone opening tools to disassemble the iPhone, take out the iPhone motherboard. Put iPhone motherboard under the Trinocular Stereo Microscope to observe, we found the iPhone display touch IC of the iPhone motherboard, iPhone light control IC U1501 and NUT column all have been removed. Moreover, the bottom of the NUT column on the iPhone motherboard has been hit by a long screw.  

Use QUICK 861DW hot air rework station and BGA remove graver to scrape it, there is no disconnection phenomenon.

Picture 1

Measuring the resistance value for the D3# layer of the iPhone display touch power supply IC U1501 by digital multimeter, there is no resistance, which is abnormal.

After check iPhone schematic diagram on the WUXINJI Dongle, we use QUICK 861DW hot air rework station to solder a jump wire from resistor R0302 to U1501D3#, and then install a good U1501.

Picture 2

After installation, measure the iPhone 6P again, now the data tested is normal.

Install the iPhone, and turn on iPhone to test, the iPhone displays properly, other functions tested also are normal, the fault has been repaired!