LG Phoenix 5 Root, bootloader unlock, TWRP, Custom ROM lmk300am

Phoenix 5 is the latest and last iteration of the LG Phoenix Series. As LG has stopped making smartphones, Phoenix 6 won’t see the light of the day.

There was a time when we used to root our phones in one click without using the computer. There were rooting apps like Kingroot. It worked until Android Lollipop. I was able to root my LG Risio 2 even with a locked bootloader.

However, Android security is beefed up over the years. Nowadays, the rooting process involves rooting the bootloader, installing TWRP, flashing a Magisk /SuperSU root via TWRP to gain root.

Let’s try to root our Phoenix 5 as per the above procedure –

How to Root LG Phoenix 5 lmk300am AT&T Cricket

To unlock the bootloader, we need to enable USB Debugging and OEM Unlock. These 2 options are found on the “Developer Options” page.

Let’s open the Settings app and go to Developer Options.

Pull down the notification panel and tap the Settings icon at the top-right corner.

Now, Go to “System” > “Developer Options” as shown above.

On the top of the page, you’ll find the option “Enable OEM Unlock”. Tap on it.

Now, hit “Enable” to allow OEM unlocking.  As long as the OEM unlock remains on, Google’s Factory Reset Protection(FRP) remains disabled.

Now, scroll down and enable USB Debugging. Hit “OK” to Allow USB Debugging as shown above.

Now, we are ready to connect out Phoenix 5 to the computer via a Micro USB cable.

A notification on the phone reads “USB Debugging connected”.

Let’s wait for the ADB Interface driver to install. Check the installation status using the Device Manager.

The LGE Mobile ADB Interface driver is installed on my PC.

For USB Debugging, we are going to use a Tool – “Minimal ADB and Fastboot”.

Let’s install and launch this tool.

The “Minimal ADB and Fastboot” tool opens the CMD window for USB Debugging.

Let’s write the first command to check the ADB connection –

adb devices 

Type the above command and hit enter on your PC keyboard.

The command output is LMK300 unauthorized 

To authorize your PC for USB Debugging, please check your phone screen.

There must an “Allow USB Debugging” request on the phone screen. Hit “Allow” to accept the request.

Now, write the same command once again

This type the out of adb devices command is LMK300 device

Our device is ready. Let’s try to put our phone into Fastboot mode for Bootloader unlocking.

LG Phoenix 5 Bootloader Unlock

The command to enter the fastboot mode is adb reboot bootloader

Type the above command and hit Enter.


With the above command, the phone just rebooted to the home screen.

Let’s try another command to access the fastboot mode.

There is one more command to boot the phone into fastboot mode –

adb reboot fastboot

Type the above command and click enter.

Our Phoenix 5 is now in the Fastboot Mode.

In this mode, the touch doesn’t work. We need to move up/down using the volume rocker and select an option with the power button.

We are interested in Bootloader Unlocking, so let’s go down from “Reboot system now” to “Reboot to bootloader” with the volume down button.

Now to select the option “Reboot to bootloader”, tap the power button once.

Unfortunately, once again the phone has landed on the home screen.

The access to bootloader unlocking is blocked on the Phoenix 5.

Without unlocking the bootloader, we cannot flash a custom recovery (TWRP). And without a custom recovery, we cannot install the Magisk or SuperSU root file.


The above image belongs to the Fastboot mode on LG K20. To unlock the bootloader we need to write the command fastboot oem unlock

LG Phoenix 5 TWRP

We have failed to unlock the LG Phoenix 5 bootloader.

With the bootloader in the locked state, we cannot flash a TWRP custom recovery.

The command line to install a custom recovery is fastboot flash recovery recovery.img

LG Phoenix 5 Custom ROM/Lineage OS

A Custom ROM is in the form of a zip file. We need to install it via the TWRP custom recovery just like Magisk/SuperSu.

As we failed to install TWRP on Phoenix 5, we cannot install a Lineage OS or any other custom ROM on our phone.

Now, that you’ve enabled USB debugging on your Phoenix 5, you may like to move the apps to SD card using the Adoptable storage feature –

How to move apps to SD card on LG Phoenix 5

1 thought on “LG Phoenix 5 Root, bootloader unlock, TWRP, Custom ROM lmk300am

  1. The Phoenix 5 also needs to have the carrier lock disabled to unlock the bootloader. you can even see where it says this right under the “enable OEM unlock” switch in the image in this guide “unavailable on carrier-locked devices”

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