I have the following situation. Bought in US LG G3 phone for a kid. Phone was stated 855 ( I live in Europe). Once I bricked him trying to revert from 5.0 to 4.4 due to huge bateery drain, it was found that actual MB model is 851 TMO.
The current situation is:
1. Phone bootloader unlocked, rooted, installed 7.1.1 Nougat, Lineage OS 14.1-20170108-UNOFFICIAL-d851 flashed with adb.
Modem is: MPSS/DI.2.0.1c1_13-00009-M89***
2. Recently purchased 4G SIM from virtual provider of Partner
3. Kid complaints on following:
- battery drains to 0 in 2 hours ( new brand battery, manufactured 8 months ago)
No applications installed - GApps pico, Chrome, Root Checker and Waze.
APN be default were set to Partner 3G portal.
I changed APN to fit virtual provider settings:
- slow surfing - I took the phone today and it indeed switches all the time between 3G and H. Talked to provider, looks like they sent me wrong SIM ( 3G flashed ).
I also see in battery usage - Mobile Strength signal - a lot of yellow lines inside green.
Network signal is HSDPA @ 7.2 Mbps
I made cross SIM test - took the SIM from a friend ( different provider and tested it with my phone) - H+ all time and Network signal is HSDPA @ 42.2 Mbps
My "blaming finger" is SIM, but Im not sure this is the main issue for battery drain.
So, I expected to get a new SIM from provider and will test it.
Q1: Am I suspicions or it can be SIM issue?
Q2: I need battery good life ROM. I'm new to LG ( mine is A0001), so I'm not sure either stay with original TMO ROM, go to AICP or else ( preferable Nougat, otherwise MM or Lollipop much better)? The most usage is surfing, WhatsApp, etc
Q3: How to set LTE correct settings? the "4636" code gives me only testing mode?
Any help will be appreciated.