[Galaxy Note Pro 12.2 Q&A, Help & Troubleshooting] dkaardal:
Model: SM-P900

OS: 5.0.2

This is an interesting one I think...

Summary

On my Note Pro 12.2, wifi cannot be enabled - it says 'turning on... ' but never actually turns on. Also, battery life (2 different batteries now) is about 2-3 hours with no apps installed or used, even if the device is on standby or totally powered off.

Background

I bought a used SM-P900 from a local guy who gave it to me for a good price because he said the devices wireless stopped being able to connect to his wifi network at home.

I took it back to my place, did a factory reset, and lo and behold everything came up fine. I could connect to my wifi network, the device was very quick and nice to use, and the battery seemed to last a good long time. I used it for a couple of weeks without any problems at all, and then one day it started having problems with the wifi connection.

Wifi issue

The unit would connect to my wireless router, but it wouldn't actually transfer data. The download arrow would flicker, but the upload arrow would not. Every so often the device would drop connection entirely, then automatically reconnect after a few seconds. Reconnection would still have the same problems - the device appeared connected, but would not actually transfer data.

After poking around the forums I decided to do another factory reset (also tried deleting cache as well). This didn't fix the issue, though it did cause a new symptom - the wifi card could no longer be found at all.

Wifi Issue #2 - wifi stuck at 'enabling'

Factory reset number 2 resulted in the device being unable to turn on wifi at all. Going through the initial setup after the factory reset, the screen where you connect to your wifi network just showed 'Turning on... ' (I think that's the text. Device isn't in front of me at the moment).

After this, regardless of any steps I take, I cannot enable wireless (or bluetooth) at all. I move the sliders and the 'turning on...' message shows for a few minutes, then the slider automatically moves back to the grey off position.

And now the battery...

After this, I noticed the battery seemed to be discharging at an alarming rate. The top back of the device would also get unpleasantly hot, and the battery would discharge at around 30% per hour - even though I'd not installed any applications at all on it, let alone run anything. This was also after I'd put it into power saving mode.

Figuring I'd come back to it the next day, I charged it up until bedtime (charge around 95%), did a complete power off of the device, and then went to bed. 5 hours later I work up and... the device was totally dead. Could not power it on regardless of anything I tried.

Flat battery, no power on... so I replaced the battery.

I bought a new battery and installed it, and now the device powers on again. Battery discharge rate is fearsome - if I power it off completely, it loses about 25% per hour. Oddly enough, if I just have it on standby it loses slightly less - around 20% per hour. This is with no applications installed (default after reset).

Tinkering with it, installing battery / CPU / process explorer apps I cannot see anything that is using much in the way of system resources. Battery capacity doesn't seem to be being reported correctly (around 3800mah) and discharge rate seems to be between -1000 and -1200

Apps I used:

CPU-Z

CPU Monitor

GSam Battery Monitor

System Panel Lite

Note: I bought a wired USB network adapter so that I could install apps on the device, since wifi is totally broken.

Troubleshooting steps tried:

Clear Cache + factory reset = cannot enable wifi (cannot find card?). Battery run flat and died.

Factory reset (x 4 or 5) with new battery installed = no effect - battery life only 2-3 hours with no use. slightly worse when device is powered off completely.

re-install OS ( Used 5.0.2 Netherlands ROM from Sammobile + ODIN) = no change

re-install OS (Used 5.0.2 Switzerland + ODIN) = no change

downgrade OS (Used 4.4.2 United Kingdom + ODIN) = no change

upgraded OS (Used 5.0.2 Netherlands + ODIN) = no change

I cannot get the wifi to enable regardless of what I do (bluetooth is the same).

I cannot get the battery to stop discharging at a very high rate, regardless of what I do (disable all non-core processes, try and track down anything using significant system resources, etc)

I've got a bunch of replacement parts on the way from China (LCD cable, charging cable, sensor cable, etc) just on the off chance it's a hardware fault with something other then a motherboard component... but does anyone have any ideas? Anyone seen this type of thing before? Wifi cannot be enabled, very high power use even after factory reset and nothing installed?

Any help at all would be very much appreciated.

:)

Donovan.