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How to Repair iPhone 6 No Display Failure


iPhone 6 does not display after starting, first connect it to the DPS DC power to check the current, the iPhone boot current test is normal, iPhone 6 turns on but the screen is not displayed. How shall we repair it?


Remove and observe the iPhone logic board under the Stereo Zoom Microscope, we find the iPhone Nand flash has been repaired before, and other parts not. However, because the iPhone Nand flash has nothing to do with the display, so we can ignore this problem.
Measure the resistance value for display socket by digital multimeter, we find the all resistance value is normal. Since the resistance is normal, then we need to measure the display power supply. Install the iPhone display screen and test it, the display +5.7V and -5.7V all are normal, but when measuring the 1.8V voltage of the display reset, no voltage was found.


After checking iPhone schematic diagram on the WUXINJI Dongle, we know that the display reset signal is directly provided by CPU, no voltage is usually caused by internal problems of the CPU.

In this situation, we need to disconnect the signal between the CPU and the display reset, and then use QUICK 861DW hot air rework station to solder a jump wire from the main reset of the CPU to the reset signal of the display. 


After completion of welding, install iPhone display and test, iPhone screen normal display, enter the IOS system, all functional tests are normal, maintenance ends!

More professional cell phone repair tools and skills please check from www.vipfixphone.com

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