Touch screen problem

[Gnopps1]

I'm having touch screen problems. For me the tablet randomly doesn't recognize touches during the below instances. In all cases either going to the home screen and relaunching the app or turning the screen off/on will solve the problem. The problems occur several times per day but not constantly.

• Sometimes opening apps will cause everything but the bottom android-buttons to be non-responsive. This can happen in any app it seems, including native ones such as Google Play.
• Sometimes the lockscreen doesn't recognize touches at all.
• While charging I've had issues getting the touchscreen to recognize, disconnecting the charger has helped.
• Double-tap to wake seems to be very moody, sometimes working sometimes not. Sometimes it turns the screen on even by me just holding the tablet with my palm resting against the screen.

While not a bug per se, but the android-buttons seem very picky that you have to hit them right on the spot to work.

[James_uk2014]

I have also noticed it seems worse when the screen is at an angle.

Why can't Sony let us know an update will be released soon to fix it? I would rather get my money back if they aren't going to fix it any time soon!

[DeGraaff]

Angles and surfaces aren't software-based. When the touch screen issues are directly affected by physical factors, that means it's a hardware flaw. No software update can correct that.

So I suggest that if you are bothered by it, just take your tablet to a sony service centre, show them the issue and ask to get it exchanged for a newer build.

[James_uk2014]

Can anyone tell me, Will the 17.1.1.A.0.438 Firmware fix the touch screen issues when its released?

Or is a fix still not likely in this fw?

James

[SergioPL1]

We will see. It's not available on my Z2 yet...

[Johan]

Hi all,

Just wanted to say that this is something that is being looked into as we speak and I will get back to you as soon as I hear anything from our developers.

But I just wanted to check how many of you that do experience this is using any case or cover on your Xperia Z2 tablet?
If yes, do you notice any difference if you remove  the case?

[James_uk2014]

I have the oficial Sony case and i dont notice any difference with the case on or off.

If my tablet screen has naturaly gone off for a bit of time after i wake it up my screen will either be frozen or the touch wont be very sensative, sometimes i will have to tap pretty hard to get it to register.

The quick fix seems to be to just pretty the power button again to turn the screen off, then press it again, and swipe to get in to it as normal, it always seems fine after doing this when it happens.

Thats my experience anyway.

Johan, are you thinking this issue is more software or hardware based, as that will impact my choice whether to keep the tablet or not.

[SergioPL1]

---

But I just wanted to check how many of you that do experience this is using any case or cover on your Xperia Z2 tablet?

If yes, do you notice any difference if you remove  the case?

---

I recently bought SCR12 official cover but it doesn't change anything (for better or for worse).

Most of the time I can live with touch responsiveness but as I mentioned somewhere earlier I do notice that (with developer tools, show touch points) sometimes touch is recognized by OS but not passed down to the application.

Other thing that I noticed yesterday and it drove me crazy was that after eating cherries I washed hands and Z2 didn't recognized my hands touch at all. My fingers felt very dry. On the other hand Xperia Z1 running KitKat 14.3.A.0.757 recognized touch without any issues. This issue went away 10 - 15 minutes later.

[DeGraaff]

Hi Johan,

I had forwarded my findings from page 4 message 40 in this topic, to xda developers and some  one there suspects that, since the touch screen precision is directly and strongly affected by the surface  on which the tablet rests, the touch screen issues are likely caused by a grounding failure in the tablet. The style cover does not seem to make a difference if the tablet is laying flat with the cover unfolded, but when using the tablet as a stand, there are issues especially with two-finger multi touch. No issues when the tablet lays flat on a glass tablet. No issues when holding the tablet in my hands. Much issues when the tablet lies on an acrylic surface. I also have an aluminum tablet stand with rubber lining all around (tablet only touches the rubber) this gives slight touch issues.

[James_uk2014]

Lol i may consider keep sending my tablet back to amazong until i get one thats a newer build

I also still have my Z1 which has recently been updated to 4.4.2, i have no issue at all with that.

[DeGraaff]

Further testing confirms that the Z2 tablet does indeed have a grounding issue:

When the tablet sits on the rubber lining of my tablet stand (pic), and I use a hand to swipe with two fingers from left to right and back repeatedly, the touch screen will regularly lose track of either finger.

Now, when I repeat this swiping, but put my hand on the backside of the tablet while swiping, the touch precision is good. But as soon as lift my hand from the backside, the issue returns.

Note that the touch issues do not occur solely with two-finger gestures, but it does seem most apparent and easiest to reproduce with two-finger gestures.

add: it looks like a person named Klaus55 also already mentioned grounding on the first page of this topic.