Install Marshmallow KDZ on LG G3 [D855] via LGFlashTool

Install Android Marshmallow KDZ on LG G3 [D855] via LG FlashTool 2014Android 6.0 Marshmallow update has been started rolling out by LG to its 2014 flagship, the LG G3. Update for D855 variant with the build number 30B is available right now and we hope that other variants of G3 will also receive the update soon. Just like all other previous updates this latest 6.0 Marshmallow update is also bundled with tons of customization and performance optimizations. While tweaking the OS under-the-hood, LG also injected their own custom skin over the stock Android OS.

The dispatching method of this latest update is same. OTA over-the-air update of Android 6.0 Marshmallow already pushed and G3 users will receive it as soon as their variant enters into the radius of OTA server. However, if you can’t wait that long and eager to try this latest Android 6.0 Marshmallow update on your device, than just hit the download button of the official KDZ firmware and then install it using the LG Flash Tool. It is most easy method to install Android 6.0 Marshmallow on your LG G3.

But before heading toward the steps, go to Settings >> About Phone >> Software Information/Updates, and check if there is any OTA update is available for your device.

If there is no OTA update listed in the menu of Software updates then head over to the tutorial below to easily install Marshmallow KDZ file on LG G3 [D855] via LG Flash tool.


  • The listed firmware (Android 6.0 Marshmallow KDZ) is only compatible with LG G3 international variant with model number D855.
  • LG Flash Tool 2014 is required to flash the KDZ firmware on your device.
  • Download the LG Flash Tool 2014 from the download section below and then install it on your PC.
  • If you got the LG Flash tool in compressed format then use WinZip, WinRAR, 7-Zip or any other unzip tools to extract the compressed file.
  • A Runtime Library of Visual C++ is required in order to launch the LG Flash Tool 2014.
  • If you have encountered any issue while installing or launching the Flash Tool then you can download and install the Runtime Library of Visual C++ from here.
  • Make sure you are using the proper and updated LG drivers on your PC or if you have not installed it yet then grab it from the download section below.

Downloads Section

  • LG G3 Marshmallow Firmware

Backup LG G3 Apps and Data

All your device data and apps will be wiped out from your current ROM if you proceed with the installation of stock firmware via KDZ file. So make sure to backup all your device important apps and data. And also transfer your device internal storage data to your PC as it may also get removed.

Install Stock Android 6.0 Marshmallow Firmware on LG G3 [D855] via LG Flash Tool 2014

Let’s start with this simple step-by-step guide to accomplish the goal of flashing stock firmware on your LG G3.

  • Step 1: First, switch to Download Mode.
  • Step 2: Turn-off your device in order to switch from normal to Download Mode, then press and hold VolumeUp + VolumeDown keys together and connect your device to PC using stock USB cable.
  • Step 3: You will see a download mode icon on the next screen.
  • Step 4: Wait for drivers to be installed on your PC.
  • Step 5: If the installation process fails at the first attempt, then repeat the process again (try holding just the VolumeUp button).
  • Step 6: Browse the folder of LG Flash Tools 2014 and copy the KDZ file in it.
  • Step 7: If the Flashtool is in compressed format then simply unzip it to get a file folder containing the required files including the LGFlashtool2014.exe file.
  • Step 8: Transfer the downloaded D855xxx_00.kdz file into the folder of Flash Tool 2014.
  • Step 9: Double-click on LGFlashtool2014.exe file.

Now you will have to do some configuration.

  • Step 10: Select Type:CDMA

Note: CDMA is the right selection! so don’t worry about it as FlashTool 2014 is modified only for SIM based devices.

  • Step 11: Select CS_EMERGENCY in PhoneMode drop-down menu.
  • Step 12: There is a folder icon next to “Select KDZ file” selection box, click on it to browse D855xxx_00.kdz file on your PC and then select D855xxx_00.kdz file.
  • Step 13: Select Type: CDMA
  • Step 14: Select PhoneMode: CS_EMERGENCY

Note: Leave the “Reset time” as it is.

  • Step 15: There are two buttons in “Upgrade with CSMG Client” section, “Normal Flash” and “CSE Flash”. You have to choose one option.
  • Step 16: If you are installing a new copy on the stock firmware, choose “CSE Flash” option to make a clean install. But if you choose this option, it is highly recommended to backup installed apps and important data first as it will format all your device apps data, system and could also wipe internal storage of your device.

Note: You can also use the “Normal Flash” option if your device in on stock firmware and you only want to upgrade and don’t want to lose any data. However, you have to make sure that your system is not modified.

LG Flash Tool 2014

  • Step 17: Once you clicked on “CSE Flash” option, a new “Read Phone Information” window will appear on screen, click on the “Start” button at the bottom of this window.

LG Flash Tool - Read Phone Information Window

  • Step 18: Select Country and Language from the drop downs and click on OK button. And also click on the “Clear phone Software update Registry”.

LG Flash Tool - Select Country and Language Window

Note: Disconnect your PC from the Internet before clicking on the OK button and if you are using Antivirus on your PC, then turn it off for some time.

  • Step 19: Once the process has started, the stock firmware will also get installed on your device.

LG Flash Tool 2014 Stock Firmware Flashing

  • Step 20: The device will automatically restart on successful installation.
  • Step 21: Now click on exit to quit the program.

LG Logo on next boot indicates that you have successfully installed the stock firmware.

If any error occurs, start again from Step 1 until success and don’t forget to disconnect your internet connection where its necessary.

Once your LG G3 boot into stock firmware, you can enjoy the latest Android 6.0 Marshmallow software.


  1. darwin March 3, 2016
    • Saud Khan March 3, 2016
    • Droid Cosmo March 3, 2016
  2. Dinesh Kumar December 21, 2016
    • Saud Khan December 22, 2016

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