Press the iPhone’s power button to turn on the iPhone, but the phone’s display does not show up and remains black. It may be that the phone is completely dead, but the phone still does not display after pressing the power button again. iPhone screen will turn black and won’t turn on no matter how many times you press the power or home button to wake up your device. What's wrong?
As we know, both software problem and hardware problem all can cause the iPhone black screen problem, after we tried some software solutions, such as force reboot, iOS update, DFU restore, the iPhone LCD Screen still keeps black, so now we can rule out software failures. Next step, we need to check iPhone display screen problem.
Check iPhone display screen, it looks good, there is no obviously damaged. We try to fix this iPhone XS black screen problem by replacing iPhone display screen.
Use screwdriver to remove the screws next to the iPhone lightning port, and then put iPhone XS on the Screen Heating Pad to heat it, so we can open the iPhone display assembly smoothly. After heating for a while, use LCD screen sucker to open the iPhone display assembly, and then disconnect those connectors that connected with the iPhone battery and iPhone motherboard, and then remove the iPhone display assembly.
Now, step by to step to install the new iPhone display assembly, and then test the iPhone XS. After booting the iPhone XS, the iPhone LCD screen still doesn't display. Seems it's not the iPhone display screen problem. Next we need to check iPhone motherboard.
Disassemble the iPhone XS, carefully remove the iPhone motherboard, the iPhone motherboard looks good, there is no obviously water damaged or drop damaged.
Use digital multimeter to measure the iPhone motherboard, the 33 pin reset displays no resistance value, while the normal value is about 370.
Run WUXINJI Dongle to check iPhone XS schematic diagram, we know that this circuit is directly to the iPhone CPU.
For this problem, the traditional method is re-installing the iPhone CPU. However, in this case, we will try a new method, we try to get the display reset circuits back to work by connecting the external component.
The route markings above the iPhone schematic diagram are clear, first we need to connect the components to each other, and then we need to solder 4 jumper wires, one connect to the ground, and the other one connect to the power supply 3.0V.
As shown in the following picture, connecting C5405, and one connect display socket 33 pin circuit to the FL4221, the last one is connected to CPU(R0802). After finishing the welding, apply some green UV oil to solidify it.
Now, use Fluke 17B+ Multimeter to measure the iPhone motherboard again, the resistance value of the reset circuit is normal.
Assemble the iPhone XS, press the power button, the Apple logo appears normally, after few seconds, the iPhone XS gets into the iOS systems properly.
I hope the repair methods in this article are helpful to you. If you have other questions about the iPhone display not displaying, please leave a message in the comments.