re: Lumia 1520 Bugs & Defects
I thought it was a firmware issue on my RM-937 White model, since I had it working fine for months after the problems started. By reading the above posts I saw the one which describes the problems seemed to do with the cover utilized. Then I noticed my issues indeed have started after I began to use a phone cover, the one that I describe in this post: Best 1520 wallet/recommendations?.
I decided to remove my phone out of the cover and for the first time I realized that while touching the upper left edge of the phone it started to behave as I was pressing the Back soft button. And sometimes it also behaves as if I had pressed the Bing search soft button. I have searched on the WPCentral forums and found several users had the same issue.
I am an electrical engineer and I have decided to open the phone and take a look since this the root cause seemed to be a hardware issue. This tutorial helped me to do that:
https://www.youtube.com/watch?v=dL2olFpWvB8
But be warned, this is not for the faint of the heart. Extremely care must be taken and I do not recommed going through this if you do not have the experience. And I have just did this because I have bought my phone in US while on vacation and it was ordered from Amazon, it is an APAC phone. In other words, no warranty in my country and no local Nokia Technical support is available.
I have just found the Nokia Lumia 1520 Service Manual on the web, which gives many more details for those interested in the guts of the phone:
http://ifixit-documents.s3.amazonaws...hSheUIDUka.pdf.
And the following is an ebay link to buying the board (also called Logic Board):
At T Nokia Lumia 1520 Windows Phone Replacement 16GB Logic Board Motherboard | eBay.
The board is described by the Service Manual as the Light Swap Package.
Well, if you look the tutorial there is the so called Engine Board. On top of that there is the main processor, which is covered by an aluminum cover, which is soldered to the main board. With the phone turned on, every time I have pressed on this cover or the very near surrounding areas I realized the Bing search popped up and the other soft buttons also behaved as if they were pressed. This board is placed over an aluminum frame and I saw that under the board there were several surface mounted components that could possibly touch the frame when the board is pressed. This is not designed to happen, but it could. If you start to press the board continuously while the phone is on, you will notice that the main processor heats a lot. This may or may not be a normal behavior, but I also saw several comments on the forums about overheating on this region of the phone. Anyway, I have decided to place a thin strips of 3M electrical tape under the board, to act as insulators and cushions, at the same time. Assembled everything and realized that the issues have gone, so far. There are no more Back/Search soft buttons issues when I press on the upper left edge of the phone. I have placed it back to the cover and it is behaving normally. However, the problem can also be related with bad soldering of the main processor. If this is the case, the problem may reapear anytime, and the root cause may just be the overheating, which is not properly being dissipated by the aluminum frame. This would lead to unreliable connection on the processor terminals, which could be triggered by the pressing action. Anyway, time will tell. So, the real fix would be replacing the Engine Board, not the Display assembly, as many thinks.
I am free of the following problems:
. Bing Search popping up
. Screen freezing
. Soft buttons not working
. Soft buttons activating randomly
. Screen shaking up and down
. Screen resizing like zooming in when going to type password on lock screen
. VGA color on lock screen
. Password undesired multiple taps on lock screen
. Phantom taps
. High Battery consumption
. SD card reading issue after a soft boot
. Reboot when shutting down
. Screen stuttering
Before the fix there was not a single hour that I did not had one or more of the above annoying problems. It's been a week now and I did not had any issue at all.
I am using Win 8.1, Glance, Double Tap to Wake, Cortana pinned to home screen and all the goodies.
Please, if anyone is willing to fix their phone, then let us know of the results.