T-mobile LG K40 X420TM User Manual / Guide

This is the official T-mobile LG K40 X420TM User manual in English and Spanish published by the manufacturer.

The LG K40 on T-mobile has the model number LMX420TM. It comes with a 5.7-inch display with a 720×1440 pixel resolution.

The T-mobile LG K40 features an Octa-Core Qualcomm Snapdragon 450 processor with 2GB of RAM and 32 GB of Internal Storage. It has a 13 MP rear-facing camera and a 5 MP front-facing sensor for selfies and video calls. Other features include a Non-Removable 2,890 mAh battery.

The T-mobile LG K40 supports 4G LTE Bands 71, as well as B2, B4, B5, B12, B13, B17, B25, B26, and B66, According to the FCC documents.

Download T-mobile LG K40 User Manual





For your information, The LG K40 X420TM from T-mobile comes with Android 9.0 Pie out of the box.  It supports Firmware update via OTA and LG Bridge.

ALL LG devices from T-mobile supports LG Bridge and LG will release stock kdz firmware for the T-mobile LG K40, So You can unbrick/restore LG K40 with LGUP Tool.

LG K40 X420TM – LG Bridge and LGUP Flash Tool:

Download: LGUP Tool 1.16 for LG K40 X420TM

LG Bridge windows: LGBridge_Setup.exe
LG Bridge Mac:LGBridge_Mac.dmg

T-Mobile LG K40 X420TM USB Drivers

/LGMobileDriver_WHQL_Ver_4.4.2.exe [Latest LG USB drivers 4.4.2] for Windows

T-Mobile LG K40 X420TM Issues:

A hard reset or master reset can fix almost all software and apps issues of T-Mobile LG K40 X420TM. Learn how to perform a reset, please refer to LG K40 User manual.

Bypass Google FRP on T-Mobile LG K40 X420TM? flashing the stock kdz firmware for T-Mobile LG K40 X420TM does not allow you to bypass the Google Account Verification process.

T-Mobile LG K40 X420TM SIM-unlock? flashing stock firmware with LGUP does not allow you to unlock your T-Mobile LG K40 X420TM. You need to use the SIM-UNLOCK APP from the T-mobile official to unlock the SIM network lock.

How to reset T-Mobile LG K40 X420TM

Hard Reset or Master Reset is always the first step to fix the kinds of software issues of your phone.

  • On the settings screen, tap General Restart & reset
  • Factory data reset:

How to boot T-Mobile LG K40 X420TM into download mode

When you want to use LGUP to sideload the stock firmware onto your T-Mobile LG K40 X420TM smartphone, You may need to get your phone into download mode first.

To enter into the download mode on T-Mobile LG K40 X420TM:

Turn off your phone, press and hold the “Volume Up” button and plug in the USB cable from your computer to the phone.

How to use LGUP Tool

Step 1,

Now connect your Phone to PC Via USB Cable and Run the LG UP Software

Wait until LGUP detects your Phone. If LG UP screen shows up, Go Step 2.

If LG UP can’t find your device, you need to put your phone into download mode manually by

Turn off your phone, press and hold the “Volume Up” button and plug in the USB cable from your computer to the phone.

Now Run the LG UP, waiting for LG UP install necessary USB drivers for your Phone.

When LG UP screen shows up. Go Step 2

Step 2, From LG UP Screen, click on the Upgrade process option

Click Bin File and Select the kdz firmware that you just downloaded

Now simply click on the Start button to begin the flashing process. Wait for few minutes until the installing process completes.

Welcome back, Now, Your phone is back to Stock. If you experience issues, please let us know in the comments below.