How To Repair iPhone 7 Touch Screen Not Working

Introduction
iPhone users may have experienced such a frustrated moment – the screen of the iPhone suddenly freezes, and it don’t response at all. So, what repair shops usually do with unresponsive touchscreen issue of iPhone 7? First of all, clean the screen. In the second place, try a force reboot of the iPhone 7. If the issue continues, try to restore the iPhone from a Backup. Still not working? The next step is to erase it and set it up as new, which means resetting it to a factory state (remember to make a backup before doing that). If none of these steps work, then the issue may be related to physical screen display defects, since everyone may have accidentally damaged their phone without knowing themselves. In such an event, broken screen repair or LCD repair could be a perfect solution.
If you’ve forcibly rebooted the iPhone 7, you’ve restored the iPhone 7 from a backup, you set up the iPhone 7 as new, and you have repaired the broken screen and LCD, and the touch screen is still unresponsive, it’s time to change your thinking and look for a totally different solution.We here present you a refreshing logic board solution regarding to the unresponsive touchscreen issue of iPhone 7.

Repair Tools:
screws


Universal Plastic Clip Fixture



Maintenance Platform

digital multimeter

Steps
1. Phone Disassembling
Turn on the phone, if the touch function is incapacitated. Remove charging port screws and detach the display assembly. Disconnect flex cables and remove logic board screws. Then take out the logic board.

2. Malfunction Diagnosing
Test resistance of the display assembly connector with digital multimeter. Resistance of pin 10 displays abnormal value (470 under normal circumstances).

Roll out the maintenance drawing for reference.

Pin 10 worked as AP_TO _TOUCH _MAMBA _CONN _L signal. The signal was connected with CPU AT2 pin via inductor FL3904.

Circuit between pin 10 and inductor FL3904 displays normally.

Test resistance from inductor FL3904 to CPU, the device displays normal value. Then we can draw the conclusion that inductor FL3904 was damaged.

3. Malfunction Repairing
Take down the inductor with soldering iron.


Solder tins on the copper wire. After that, connect the two bonding pads of the inductor with the copper wire. Then cut off the rest of it with a sculpture knife.

Test pin 10 resistance with digital multimeter again, this time we get a normal value, which means the problem has been fixed.

4. Function Testing
Clean the bonding pad with PCB cleaner.

Assemble the phone and test. Touch function is back to normal.

Comments

Post a Comment

Popular posts from this blog

Slove iPhone X Won't Turn On

Image
Customer delivered a iPhone X and described the fault is not to boot after the phone drop accidentally. It reports error 56 when restore the iPhone X. How to repair this fault? Because iPhone X is the two board connected through the middle column, it is easy to drop the point. It may be that the solder points from NFC chip to the CPU part have fell off. Take apart the iPhone X by iPhone Screwdriver Repair Tools , take the upper board off the main board, when separate the main board we see a row of points have fell off. Picture 19-3-1 Look at the location map on WUXINJI dongle , it is surrounded by a ground wire, in fact, there are 6 useful points dropped. The ground wire does not need to be filled, the 6 useful points are added by professional phone welding tools. These are the signal wires of the NFC chip, so the iPhone X would report error 56. Picture 19-3-2 Then the tin of the middle column is repaired by iPhone X BGA reballing stencil , and the AP part is welded bac...
Read more

Setup and install the zxw tool Dongle Wizard

Image
So, you recently purchased ZXW Tools from our vipprog online store have no clue how to set it up?  Well, here is a quick guide detailing the installation process. Step 1 Unbox the ZXW tools dongle and plug it into your Windows PC.  ZXW tools does not support Mac at this time, so you’ll need a Windows compatible box. Step 2 Download the ZXW Tools software [direct link].  The ZXW tools website is in Chinese, but lucky for you, we’ve made it easy for you to download the latest version of their software directly from our website.  The zip file contains all of the files necessary to run ZXW Tools (trace) and Blackfish (schematics).  There is no installation process.  You just need to copy the files over to a directory on your desktop. Step 3 After you’ve copied all of the files over to a folder on  your desktop, then just run the ZXW tools executable.as shown in the picture. When your first run the software, the program will ask yo...
Read more

IPhone 6P Front Camera and Distance Sensor Fault

Image
Received a iPhone 6 Plus, the customer said that the front camera can not be used, and the distance sensor has problem too. The two failures are concentrated on the front camera flex cable, which is likely to be caused by the damage of the wiring. First, we have to eliminate the possibility of the external parts fault, then consider the motherboard problem. Remove the screen assembly and replace it with a good one, we still can't turn on the front camera and use the distance sensor. Disassemble to measure the ground resistance of the front camera seat of J1111 by Fluke digital multimeter , it is found that several pins are infinitely large, and the related inductors are loose when touch with the pen. It seems that the small components are pseudo welded. 19-1- 1 Remove the motherboard and observe it under the Trinocular Stereo Microscope , we can see that the touch was repaired before. 19-1-2 The back of the sub touch chip U2402 is the front camera seat J1111, an...
Read more