iPhones are pretty useless when the touch screen doesn’t respond. Trying to troubleshoot the issue is even more difficult. The issue happens when either the software itself is preventing the OS from talking to the hardware. Sometimes it is a hardware issue where something loses contact internally or some kind of damage has occurred. Let’s start with handling the software issues.
See Also: How to Fix: iPhone 6s Touch Screen Periodically Unresponsive
In order to troubleshoot and get anything going on the software end of things, a hard reset will be necessary. Hold down the power and the home button until the Apple icon appears on the screen. This means the phone is restarting. Once the phone is back, see if you can unlock your phone and reach the home screen. If so, then it is possible that something software related is causing your phone to freeze up.
Try to open the last few apps that you were using when the touch screen became unresponsive. In other words, try to recreate the problem. If you are able to, then remember the app that you were in and hard reset the phone again. Try deleting that app by going to the home screen, holding your finger over the app until the icon starts to shake an a little ‘x’ appears in the corner of the app. Press the ‘x’ and then delete the app as the menu asks. Delete the app and then try reinstalling it from the app store.
If you use the app again and the issue reoccurs, goto the iTunes store and look for the option to message the developer and tell them of the issue.
If you hard reset your phone and none of the apps are causing the problem and the touchscreen still doesn’t work, place your iPhone in DFU mode. This is called the Default Firmware Update mode. This basically takes all data off the phone and uses the factory installed firmware version to start the phone.
Hook your phone up to your PC and connect to it using iTunes. When iTunes recognizes your phone, click on it. Then you should see a button that says ‘Restore iPhone’ next to ‘Check For Update’. Click that and allow the process to run. Once complete, you will need to re-download your desired apps and other info (pics and/or music) from your iCloud.
The last ditch effort this side of opening up your phone is to try to ‘massage’ the internal touchscreen connections back into place. See the picture below and use your thumb to press down a bit (not enough to crack the screen mind you), and firmly rotate your thumb about in hopes of ‘reconnecting’ the connection. If it works, the screen should respond again.
If this trick doesn’t work, it may be time to take the phone to a iPhone repair shop to have them replace the logic board or fix the connection.
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