OK, I have found the issue that causes the touchscreen ghost touches, unresponsive touchscreen, etc. This guide is short and simple, and is provided with NO WARRANTY, TO BE FOLLOWED AT YOUR OWN RISK. This guide requires that you open your device WHICH VOIDS THE WARRANTY. Those of us with the original grouper/WiFi/2012 version are well outside our warranties, so that really doesn't matter now.
To explain, our devices use (to my knowledge) an actively driven capacitive touchscreen sensor. It has been narrowed down that a significant number of devices suffer from a grounding issue where the voltage potentials between the case and screen will cause a number of touchscreen issues when the device is electrically insulated from the person touching the screen. There are many YouTube videos and guides on how to diagnose if your touchscreen has this issue; I will not detail those here. To be simple, if you set your device on an insulated surface like a wood table and touch the screen with ONE HAND while not touching the device with your other hand, the touchscreen will go ape**** on you.
For those of us suffering these issues, it can ruin the entire experience of the tablet. I have deduced through a logical process the location and cause of this issue, which I will detail in the guide below.
The nexus 7 uses a filmed metal back, which is mechanically grounded to the motherboard via two "blind" gold spring contacts on the motherboard which touch the filmed metal backing of the case back. I call these "blind" contacts because there is no corresponding electrical contact for them to sit upon, simply the material of the case itself is what they contact when the case is closed.
What you will do by following this guide, is physically break these tabs off the motherboard, thereby breaking the circuit of the faulty ground point. The reasons this is successful in resolving the touchscreen issue appear to be twofold; first the ground points wear off the filmed metal of the back QUICKLY due to flexion of the plastic case back and therefore end up forming a SECOND capacitor on the device case back. This causes electrical potential to build between the plastic case back and the device itself, causing unreliable reading and operation of the capacitive touchscreen. Second, the intermittent ground connection causes unreliable grounding of this capacitive potential, which is worse than no ground at all in the respect of a capacitive coupling of the case back and the device.
These issues could not and cannot be resolved by a firmware flash, because it is a physical problem. Asus could not resolve the issue completely, because even if all components involved are replaced the issue will arise again due to the way the device is constructed. It was simply a poor design.
So, to get to the meat and potatoes of the fix;
1.) Pop the back off your nexus 7. Locate and REMOVE THE BATTERY CONNECTOR to prevent any possibility of a short while you follow the rest of the guide.
2.) Locate the two blind gold spring pins on the bottom right corner as circled in red on my attached picture. Note how they do not have any corresponding connection on the case back as the WiFi GPS Bluetooth and NFC antennas do. This is because these points were meant to found the case back to prevent exactly the issues we are seeing. However due to poor design they have become the CAUSE of the issue.
3.) Most simple step: break BOTH connectors completely off the board by gently bending them back and forth until they snap cleanly off the board. There is no chance of trace damage when doing this - the solder is MUCH stronger than the super thin spring connectors and they will easily break cleanly at the solder joint. If you do not break BOTH off, the touchscreen will get WORSE because you have simply enhanced the ability of the case back to form a capacitive coupling with the case back. So break both, or do not bother.
4.) Replace the battery connector and case back, ensuring you do NOT damage any of the other fragile gold spring connections, if you do you will lose some of your antennas and these connectors are a pain in the ass to replace.
I have attached a picture that shows the two points that need broken off the board circled in RED.
That's it, you're done. Reboot the device and enjoy a touchscreen that actually ****ing works. You're welcome.
Again this guide is provided at your own risk, I am not responsible for anyone who breaks the wrong connector despite my detailed guide, and I am not responsible for any other damage your fat fingers might cause while dicking around inside a sensitive electronic device.
I understand if some are too squeamish to attempt this guide, but I respectfully request that those afraid to attempt do not bother ****ting up the thread with useless posts. Constructive comments are always welcomed.
If this works for you as it did for me (I.E. perfectly) please hit the THANKS button!
I'm also currently unemployed, so if I've helped you and you are better off than I am then donations to my google wallet account are HUGELY APPRECIATED!
To explain, our devices use (to my knowledge) an actively driven capacitive touchscreen sensor. It has been narrowed down that a significant number of devices suffer from a grounding issue where the voltage potentials between the case and screen will cause a number of touchscreen issues when the device is electrically insulated from the person touching the screen. There are many YouTube videos and guides on how to diagnose if your touchscreen has this issue; I will not detail those here. To be simple, if you set your device on an insulated surface like a wood table and touch the screen with ONE HAND while not touching the device with your other hand, the touchscreen will go ape**** on you.
For those of us suffering these issues, it can ruin the entire experience of the tablet. I have deduced through a logical process the location and cause of this issue, which I will detail in the guide below.
The nexus 7 uses a filmed metal back, which is mechanically grounded to the motherboard via two "blind" gold spring contacts on the motherboard which touch the filmed metal backing of the case back. I call these "blind" contacts because there is no corresponding electrical contact for them to sit upon, simply the material of the case itself is what they contact when the case is closed.
What you will do by following this guide, is physically break these tabs off the motherboard, thereby breaking the circuit of the faulty ground point. The reasons this is successful in resolving the touchscreen issue appear to be twofold; first the ground points wear off the filmed metal of the back QUICKLY due to flexion of the plastic case back and therefore end up forming a SECOND capacitor on the device case back. This causes electrical potential to build between the plastic case back and the device itself, causing unreliable reading and operation of the capacitive touchscreen. Second, the intermittent ground connection causes unreliable grounding of this capacitive potential, which is worse than no ground at all in the respect of a capacitive coupling of the case back and the device.
These issues could not and cannot be resolved by a firmware flash, because it is a physical problem. Asus could not resolve the issue completely, because even if all components involved are replaced the issue will arise again due to the way the device is constructed. It was simply a poor design.
So, to get to the meat and potatoes of the fix;
1.) Pop the back off your nexus 7. Locate and REMOVE THE BATTERY CONNECTOR to prevent any possibility of a short while you follow the rest of the guide.
2.) Locate the two blind gold spring pins on the bottom right corner as circled in red on my attached picture. Note how they do not have any corresponding connection on the case back as the WiFi GPS Bluetooth and NFC antennas do. This is because these points were meant to found the case back to prevent exactly the issues we are seeing. However due to poor design they have become the CAUSE of the issue.
3.) Most simple step: break BOTH connectors completely off the board by gently bending them back and forth until they snap cleanly off the board. There is no chance of trace damage when doing this - the solder is MUCH stronger than the super thin spring connectors and they will easily break cleanly at the solder joint. If you do not break BOTH off, the touchscreen will get WORSE because you have simply enhanced the ability of the case back to form a capacitive coupling with the case back. So break both, or do not bother.
4.) Replace the battery connector and case back, ensuring you do NOT damage any of the other fragile gold spring connections, if you do you will lose some of your antennas and these connectors are a pain in the ass to replace.
I have attached a picture that shows the two points that need broken off the board circled in RED.
That's it, you're done. Reboot the device and enjoy a touchscreen that actually ****ing works. You're welcome.
Again this guide is provided at your own risk, I am not responsible for anyone who breaks the wrong connector despite my detailed guide, and I am not responsible for any other damage your fat fingers might cause while dicking around inside a sensitive electronic device.
I understand if some are too squeamish to attempt this guide, but I respectfully request that those afraid to attempt do not bother ****ting up the thread with useless posts. Constructive comments are always welcomed.
If this works for you as it did for me (I.E. perfectly) please hit the THANKS button!
I'm also currently unemployed, so if I've helped you and you are better off than I am then donations to my google wallet account are HUGELY APPRECIATED!
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