Touch screen misbehaving

[Slivovidze]

Hi,

I just got a new (yes, new - package intact) Z1 Compact.

It had Android 4.3 installed. Touchscreen behaved funny. On drag, it would often stop registering touch for a moment and immediately register it again, but not as a drag, but as a tap. It happened very often. While browsing the internet, I kept opening links I didn't want to, while scrolling in contact list I kept calling people I didn't want to, while browsing Facebook I issued likes I didn't intend to, etc. It happened randomly all around the screen.

Then I upgraded to Android 5.1.1 through Xperia Companion. The problem was fixed, but another, similar, emerged.

Now when I operate the phone, the screen often registers touches when I'm not touching it. They are just short taps and they seem to all concentrate in the top 1/3rd of the screen. The frequency of this seems to depend on what I'm doing. When I'm just dragging on the homescreen, it happens rarely and I can't reliably reproduce it. While browsing internet it happens quite often, clicking links I didn't want to click. Even more often on Facebook, also it is very annoying when I'm typing message - it clicks in the upper part of the display, which is out of the keyboard, so the keyboard disappears. And it was the worst when the phone was busy a lot - while downloading and installing apps, I pretty much had to keep my finger on the screen somewhere or it would click me away from where I wanted to be.

I tried checking it in Sketch and indeed, when the phone was busy a lot, it had "seizures" and it kept making dots randomly all over the upper third of the screen. After several seconds the seizure ends, but when I do something (drag a line, or pull the top bar down) it often gets another fit.

Doing research, I activated developer options and activated the "show point coordinates" - now my last touch/drag leaves a track on display, so I know when it the problem occurs - my track disappears, as there was another touch registered.

Doing more research, I activated the service menu (by dialling *#*#7378423#*#*) and went to service tests and touchscreen test. Curiously, during this test it seems like the problem doesn't occur. I can paint around all I want and my track stays highlighted.

What should I do? I thought it could be faulty hardware, but since the behavior changed when I updated my software, I wasn't sure. Now after the service touchscreen test I am thinking that it could be a software problem.

Any ideas on how to fix it?

Thanks!

[NeoBeum]

Go to the store and tell them to give you a new one

[Slivovidze]

Not really an option, since it seems like I got the last new Z1 Compact in my region

Sure, I could play it on warranty, but the chance of getting a new one is rather slim and I'd prefer having this phone (I bought it for reasons) over having to choose another one.

[NeoBeum]

RMA - wait for one of the Sony reps to post

[CameronT]

Hi @Slivovidze,

Welcome to the community. I am sorry to hear about your experience with your new Z1.

You could always try a software repair using Xperia Companion, this will re-install the firmware of the phone. If the issue is being caused by the update, this should fix it.

If that does not resolve the issue then the best thing to do is to contact your Local support team to discuss a warranty repair.

[Slivovidze]

Sadly the software repair didn't do, so guess I'll have to try the warranty.

Thanks for the link.

Just a side thought. While looking throught the internet for some solution, I found that someone got it fixed by ripping the factory protective foil from display. Or someone else got an improvement from applying additional protective screen. 

Are any of these possible? I don't really consider ripping off the factory one, but buying a new foil is doable and not that expensive. Does anyone have experience with the protective glass/foil improving touchscreen performance or fixing problems?

[CameronT]

@Slivovidze,

The factory protective film is the one that is loosely attached and easy to remove. Do not tear off the one that is built into the screen as you will void your warranty.