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Fixed: iPhone 6S No Display after Turning On


The iPhone 6S we are going to fix has no display after turning on, it accidentally dropped into water before, after drying it, we press the iPhone power button, after for a while, the screen still is black, we try to use another iPhone to call it, the phone has response, but the iPhone screen still doesn't display. How to repair this kind of fault?


Disassemble the iPhone 6S by phone opening tools, and carefully remove the iPhone logic board. 
Connect iPhone to the DC power supply to measure its starting current, the current tested is normal, no large current failure, now we need to check if it has a display but no backlight. Check it under the light, we find the iPhone has a display.

Use Fluke 15B+ Digital Multimeter to measure the display socket, some pins are corroded, but the resistance value data is tested normal. We need to take off the CPU shield, we found that one end of this capacitor was seriously corroded.

Check iPhone schematic diagram in the WUXINJI Dongle, this component is responsible for backlight power supply. Carefully remove it by QUICK861DW hot air rework station, and then install the new one.

Measure it again, now the backlight displays normally, all functions tested are normal.

Get more technical support for iPhone repair from www.vipfixphone.com

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