If you have a Sony smartphone or tablet, you may have come across the dreaded erratic screen issue. My Sony Xperia Z2 tablet happened to suffer from this particular bug that rendered nearly anything that required scrolling an exercise in absolute frustration. Restarting… no help. Update… not available. So, how do you resolve this issue when Sony winds up slow on the release of updates and there isn’t an app for that?

After plenty of poking around, I managed to find a solution that worked for the Z2. I can’t promise that this solution will work for every erratically behaving Sony mobile device, but it’s always worth a try.

In the Sony line of Android devices, there’s a handy diagnostic tool. Within that tool, you’ll find diagnostics for the camera(s), charging, vibration, buttons, screen, and sound.

Within the Screen diagnostics, you’ll find a Touchscreen tool that tests whether the touchscreen is working properly. Strangely enough, when that touchscreen passes the test (and it should, even when the scrolling is out of whack) the erratic scrolling disappears.

Here’s what you need to do:

  1. Open Settings
  2. Tap About Phone | About Tablet | Diagnostics
  3. Scroll down to the Screen section
  4. Tap Touchscreen
  5. When prompted, tap Test

When the screen goes black, start drawing with your finger (Figure A).

Figure A

Using the Touchscreen diagnostic tool on a Verizon-branded Sony Xperia Z2.

After a bit of drawing, a new pop-up will appear, asking if the screen copied the movement of your finger. Tap yes, and you’re done. At this point, the scrolling of your tablet should now behave properly. If not, reboot the tablet and run the test again.

Note: If you’re using a Sony smartphone, you’ll tap About Phone | About Phone | Diagnostics.

If you reboot and re-test your device and it still behaves erratically, you should do a factory reset and then refuse updates until Sony permanently resolves the issue in the firmware.

Have you discovered a smartphone or tablet behaving badly? If so, what was the make/model, and what was it doing? Share your experience in the discussion thread below.