Touchscreen unresponsive from time to time
Sometimes my touchscreen is unresponsive while using the phone. When it happens, I have to lock it and unlock it. Sometimes, when locked, the touchscreen doesn't answer too. So I have to leave the phone alone for a few minutes and try again later.
I have tried:
- Restarting the phone with Home+Power buttons (10s)
- Restoring the phone
- I have read that the touchscreen connector could be lightly disconnected. But this problem happens either I use the phone in my hand or placed on a table.
- I made some tests using the calculator app. When the problem occurs, the gyroscope still works since I can flip the phone and use the calc in portrait/landscape mode.
- All the buttons (volume, power, home, even handfree kit) works too
Of course, the phone fell down a few times but nothing harmful.
How can I test either it's an iOS or hardware issue ?