Stop Your Screen From Turning Off with KeepItOn

We all know the feeling of reading a news article orrather longdocument, when our screen … more

The XDA LG QPair Developer Challenge Voting Has Begun!

It seems like it was just yesterday that weannounced that we had paired up with LGto … more

Major Update for the Sony Smartwatch 2 Brings DND and More

With the wearables landscape now dominated by Android Wear and Pebble, its … more

How to Root Android Wear 5.0.1 Lollipop Devices – XDA TV

The Lollipop update for Android Wear devices has hit the market and people are … more

Welcome to XDA

Search to go directly to your device's forum

Register an account

Unlock full posting privileges

Ask a question

No registration required
Post Reply

How to fix ghost touches or phantom touches in nexus 7 2012

OP KRAKENŽ

11th August 2014, 10:35 AM   |  #1  
KRAKENŽ's Avatar
OP Junior Member
Flag MUMBAI
Thanks Meter: 1
 
6 posts
Join Date:Joined: Aug 2014
More
Many users including me have faced this issue,the tablet screen automatically starts showing surface touches without any human intervention!!!!
so if you are looking for a fix to this issue you are on the right thread

Here are few things that worked for me and probably will work for you too
1.lock your tablet and open it again (ie make the display go to sleep for a while)

2.Reboot your device

these were the basic steps that might help but still if you get phantom touches refer further ;

This is the most important step that helped me and many users
*Go to settings>developer options>force GPU rendering (force use GPU for 2d drawings) click on it and enable it.
reebot your device

I cannot guarantee that doing the above procedure will fix all your touchscreen issues but as far as phantom touches are concerned it might help
The Following User Says Thank You to KRAKENŽ For This Useful Post: [ View ]
11th August 2014, 07:42 PM   |  #2  
Senior Member
Thanks Meter: 199
 
538 posts
Join Date:Joined: Sep 2012
More
to force GPU rendering is IMHO useless because all system apps and most play store apps use 2D GPU rendering already. This option is only there for developers who want to test their apps with 2D GPU rendering.
15th August 2014, 03:40 AM   |  #3  
USBhost's Avatar
Senior Member
Flag u:r:usbhost:s0
Thanks Meter: 1,215
 
2,630 posts
Join Date:Joined: Oct 2013
More
Quote:
Originally Posted by KRAKENŽ

Many users including me have faced this issue,the tablet screen automatically starts showing surface touches without any human intervention!!!!
so if you are looking for a fix to this issue you are on the right thread

Here are few things that worked for me and probably will work for you too
1.lock your tablet and open it again (ie make the display go to sleep for a while)

2.Reboot your device

these were the basic steps that might help but still if you get phantom touches refer further ;

This is the most important step that helped me and many users
*Go to settings>developer options>force GPU rendering (force use GPU for 2d drawings) click on it and enable it.
reebot your device

I cannot guarantee that doing the above procedure will fix all your touchscreen issues but as far as phantom touches are concerned it might help

yep thats what i did if i got it
but the GPU rendering i did not try
15th August 2014, 09:59 AM   |  #4  
KRAKENŽ's Avatar
OP Junior Member
Flag MUMBAI
Thanks Meter: 1
 
6 posts
Join Date:Joined: Aug 2014
More
Quote:
Originally Posted by USBhost

yep thats what i did if i got it
but the GPU rendering i did not try

I can't give the reasons how 2d rendering works but it worked for me and I have searching for other possible reasons for phantom touches here is another possible reason
1.open your back panel, look at the right side,there is a black piece of foam tape on the cable attached to the touchscreen. when touching this tape or slightly pushing
down on this part of the device touch input starts to go crazy. I have noticed this also happens when the cover is closed and
you push down on the spot where the tape is.
So this probably means the ribbon cable gets flexed too much or maybe shorts when pressure is put on the back of the
tablet.
Put a little piece of plastic right under where ribbon cable comes up from the screen
and you are done

WARNING: Be careful or you might screw up,I will not be responsible if you spoil your Nexus
15th August 2014, 10:53 AM   |  #5  
USBhost's Avatar
Senior Member
Flag u:r:usbhost:s0
Thanks Meter: 1,215
 
2,630 posts
Join Date:Joined: Oct 2013
More
Quote:
Originally Posted by KRAKENŽ

I can't give the reasons how 2d rendering works but it worked for me and I have searching for other possible reasons for phantom touches here is another possible reason
1.open your back panel, look at the right side,there is a black piece of foam tape on the cable attached to the touchscreen. when touching this tape or slightly pushing
down on this part of the device touch input starts to go crazy. I have noticed this also happens when the cover is closed and
you push down on the spot where the tape is.
So this probably means the ribbon cable gets flexed too much or maybe shorts when pressure is put on the back of the
tablet.
Put a little piece of plastic right under where ribbon cable comes up from the screen
and you are done

WARNING: Be careful or you might screw up,I will not be responsible if you spoil your Nexus

Don't worry I soldered to the bord of my tablet 3+ times
But I don't seem to get phantom touches anymore
Well once evey 2 months or so. I'm fine
6th September 2014, 12:23 PM   |  #6  
Junior Member
Thanks Meter: 2
 
15 posts
Join Date:Joined: Jun 2012
More
Theoretically it dosent help because its a hardware problem.I have ever met that probelm and fortunately my tablet was in warranty that time then i sunk help to ASUS.I witnessed how they solve the probelm:They cable-flashed a screen aligning rom into it and callibrated.Then they flashed the stock rom and everything is Okay now.youd better call the supporting center.
8th September 2014, 11:37 AM   |  #7  
KRAKENŽ's Avatar
OP Junior Member
Flag MUMBAI
Thanks Meter: 1
 
6 posts
Join Date:Joined: Aug 2014
More
Quote:
Originally Posted by AqCwW

Theoretically it dosent help because its a hardware problem.I have ever met that probelm and fortunately my tablet was in warranty that time then i sunk help to ASUS.I witnessed how they solve the probelm:They cable-flashed a screen aligning rom into it and callibrated.Then they flashed the stock rom and everything is Okay now.youd better call the supporting center.

There are many possible reasons to have phantom touches on screen let me explain
Capacitance has little to do with conductivity and virtually no electrons actually cross the
capacitance gap (think insulator). It is a measure of a change in the electromagnetic field around
the anode and cathode...causing a change in the difference of pressure between negative and
positive electrons on those competing surfaces separated by an insulator (or ambient charge).
By bringing something capable of either holding a static charge, conducting electricity or otherwise
affecting the measured capacitance (electromagnetic field) near it, the capacitance changes and this
is how it determines where the screen is being touched. It doesn't have to actually contact (or
conduct) which is why you can place a thin cloth or piece of paper over the screen and still activate
it.
Don't believe me? Try it. Put a piece of printer paper over the screen and then try to select an app.
Don't be too shocked when it loads. Another test , even more revealing to prove it... Put your phone
in a zip-lock bag (the plastic bag doesn't conduct electricity), and zip it closed. Then watch in
amazement as the phone's touch screen works perfectly inside the bag. If this weren't true, then
screen protectors wouldn't work unless they conducted electricity.
Moisture, grease, dirt...even dust changes the capacitance and can create an unstable reading such
that it can detect "ghost" touches, or real touches can be distorted fooling the digitizer into thinking
it has more than one press going on (this is a multi-touch screen digitizer), or that the actual press
is somewhere else on the screen.
Voltage fluctuations and "dirty power" such as produced by lower quality wall adapters can also
cause similar results. There are plenty of threads on the subject.
In your case, it was obviously hardware, but just because you identified and resolved your issues
regarding hardware, doesn't mean anyone else who offers an alternative potential cause is a "weirdo". By making blanket statements like that one, you effectively rule out all but your own
hypothesis, and then you make yourself look like the "know-it-all weirdo".

Post Reply Subscribe to Thread
Previous Thread Next Thread
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes