How to Downgrade the LG G3

Stock LG G3

Unless you bought the LG G3 before a certain date, you most likely have a version of Android that can no longer be rooted. So today I wanted to take you through the step by step guide on how to downgrade your LG G3 so you can root it.


When a new device comes out the hackers and coders dive in and try to find an exploit. It’s this exploit that allows us to gain root access, which allows us to unlock the bootloader, which allows us to install a custom recovery, which allows us to install a custom ROM. As these exploits become public, the Android OEMs usually try to patch that exploit as soon as possible. The hackers can either try to find another security hole to exploit or the community can come up with a way to downgrade. This is what I’m going to show you today.


Since most of the LG G3 smartphones that are sold today are running a version of Android that is no longer exploitable, I’m going to show you how to downgrade your LG G3 back to an older version of Android. Once you have downgraded to an earlier version of the Android firmware, you can then use the root tool that the community has been using for a while. I do not have a list of which versions of the LG G3 firmware is rootable or not. If you are a new owner of an LG G3 then I suggest you check out the how to root the LG G3 article and see if you can gain root access to it.


If you cannot get into the LG G3 with Stump then you’ll want to follow this guide on how to downgrade. This tutorial is actually very similar to the how to revert the LG G3 to stock article that I wrote about not too long ago. The premise is the same though, we’re just going back to an older version of the firmware and this just happens to be the stock LG G3 firmware too. Once you go back to an older version of the Android firmware, you can root it, unlock it and then install a newer version of Android.


[box type=”warning”] Downgrading your version of Android is essentially like a factory reset. You will lose all of your data and it will be like you had just pulled the phone out of the box brand new.[/box]


Downgrade LG G3

  1. Power Off the LG G3
  2. Plug in a Micro USB Cable into Your Computer
  3. Press and Hold the Volume Up Button on the LG G3
  4. Plug in a Micro USB Cable While Still Holding the Volume Up Button
  5. Wait Until You See a Firmware Update Screen
  6. Let Go of the Volume Up Button
  7. Press the Windows Key on Your Keyboard
  8. Search for Device Manager and Open it
  9. Locate the COM & LPT Ports Option and Expand it
  10. Make Sure You See LGE Mobile USB Serial Port
  11. If You Can’t, Download the LG USB Drivers and Install Them(and then restart your PC)
  12. Double Click LGE Mobile USB Serial Port
  13. Click Port Settings
  14. Click Advanced
  15. Change the COM Port Number to COM41
  16. Click OK and then Click OK Again
  17. Download LG FlashTool
  18. Extract LG FlashTool and Install
  19. Do Not Run LG FlashTool When it Finishes Installing
  20. Navigate to the Extracted LG FlashTool Folder
  21. Copy and Paste the MegaLock.dll File to C:\LG\LGFlashTool (assuming that is where you installed it)
  22. Download the Stock Firmware for Your Specific LG G3 Model
  23. Extract the Stock Firmware File to Your Desktop
  24. Open LG FlashTool
  25. Click on Manual Mode
  26. Click the “…” Button at the Top Right
  27. Locate the .DLL File from the Firmware Download Page
  28. Click Add
  29. Locate the .TOT File from the Extracted Firmware Folder
  30. Click OK
  31. Click the Yellow Arrow at the Top Left
  32. Wait Until the Gray Box in the Middle Disappears
  33. When You Have One Yellow Box that Says Ready(all other boxes say disabled)
  34. Unplug the Micro USB Cable from the LG G3
  35. Plug in the Micro USB Cable Back into the LG G3
  36. Let LG FlashTool do its Thing
  37. After ~5 Minutes the LG Flash Tool Should Say “PASS!!”
  38. If You Have a Blue Screen on Your LG G3, This is Good
  39. Blue Screen Should Say “Factory Reset Status” with the Number 3
  40. Unplug the Micro USB Cable from the LG G3
  41. Remove the Battery and then Replace it
  42. Power the LG G3 Up
  43. You Should See the LG G3 Boot to the Setup Screen
  44. This Means You are Back to the Stock Firmware with No Root


Note – I am getting feedback from Reddit user /u/codytheking and he is telling me that he had to change his Action Mode option(in LG FlashTool) from ‘Upgrade DL’ to ‘Board DL'(right before step 30). If I could get more people to give me feedback on this option to help confirm or deny this then I will add it into the tutorial if needed.

I’m also getting feedback that this should be performed with a USB 2.0 port. If you are trying this with a USB 3.0 port then you will most likely get errors(although, I just received a comment saying that they were able to get it working with USB 3.0). Remember, you should be using the original USB Cable cable that came with the LG G3 as generic ones can give you errors as well

Another user wanted me to warn you that between steps 36 and 39 that “your phone may do some weird things, be patient and wait for the blue screen” :)

More feedback has come in from a T-Mobile user who says “I tried this method again and after downgrading I was stuck with the same problem (Sim card not working). While my phone was still in the initial set up mode (sim card not working) I plugged my phone back into my computer. Almost instantly the sim card started working and I am now fully connected to T-mobiles 4g LTE network”. So you might want to try this in case you run into the same issue.


The first thing we need to do is to get your LG G3 into Download Mode. Getting into Download Mode on the LG G3 allows us to install a fresh firmware onto the device with the LG FlashTool program. In step 22 I link you to a list of stock firmwares for the LG G3 courtesy of Android Rootz. When you visit that page, scroll down to the bottom and download the one that matches the model of your LG G3. Since I have the AT&T LG G3, I would click the D850 link and download both the zip file and the dll file that is listed on that page.


The rest of this tutorial is basically just setting up LG FlashTool properly. It can be confusing at first but you quickly start to get used to it. Since you’re following along with this tutorial step by step, it shouldn’t be too difficult. As always, if you have any questions then scroll down to the bottom of this article and leave a comment. I will always try my best to help everyone that I can. If something in the tutorial doesn’t match up properly with what you are doing then it is better to ask than to guess.


Once you have installed the original firmware file for the LG G3 onto your device, then you can follow the guide on how to root the LG G3. Once you are rooted you can follow the guide on how to unlock the LG G3. Unlocking the bootloader of the LG G3 will install a custom recovery(TWRP) and this is where you can perform your first Nandroid backup. It is always recommended that you backup your device before you start to install any custom ROMs, custom kernels, or modifications that require root access.


[box type=”info”]If this worked or didn’t work for you, please leave a comment at the bottom of this article to let me know. This will help me to keep these tutorials up to date so no one runs into any issues.[/box]


If you get the error Factory Status 2, maybe this tip will help you get through it.


About the author


I'm working to create an organized and easy to follow central repository of Android tips, tutorials, guides and everything you need to know. With a focus on device specific tutorials now, my goal is to branch out and do more universal tips and tricks that will work on all Android devices.