Like any other Nexus device, the Nexus 6 also comes with an unlockable bootloader and not an unlocked one. The difference between the two is pretty minor on paper but makes a lot of difference when you try to gain root access or install a custom recovery on the device.
An unlockable bootloader is technically locked in the first place but can be unlocked, while an unlocked bootloader was never locked in the first place, which means you can directly proceed to gain root access on it.
Thus, if you are looking to root or flash a custom recovery on your Nexus 6, you will have to unlock the bootloader of the device first. The steps to unlock the bootloader on the latest Nexus device are largely similar to its predecessor except for a small change.
Before you proceed with the steps below, make sure to create a backup of all your data since unlocking the bootloader will wipe your handset clean. This includes your messages, contacts, videos, apps, app data, music, images and any other files stored on the internal storage of the device.
Download the files
Step 1: Download the ADB drivers for Windows and the correct version of ADB/Fastboot for your PC from below.
Extract the contents of the ADB/Fastboot ZIP file inside a folder called “nexus6” on your desktop. Windows users will also need to install the drivers and restart their PC before they can proceed further.
Step 2: On your Nexus 6, go to Settings -> About Phone and tap the ‘Build Number’ option seven times to enable Developer Options. Now, head over to Settings -> Developer Options and check the ‘Enable OEM unlock’ option.
Reboot to Fastboot mode
Step 3: You will now have to reboot your Nexus 6 into Bootloader (a.k.a Fastboot mode) so that you can execute the Fastboot command to unlock its bootloader. To do this, switch off the handset, and then press the Volume Down + Power button simultaneously for a few seconds.
Step 4: Connect the device to your PC and start a new Command prompt or Terminal window on it. Use the ‘cd’ command to navigate to the nexus6 folder on your desktop. The below command should work for the majority of the users:
Alternatively, you can simply drag ‘n’ drop the nexus6 folder to the Terminal or Command Prompt window as well.
Unlocking the bootloader
Step 5: Run the following command to first make sure that the Nexus 6 is being detected by your PC.
Mac users, you will need to prefix a “./” before every Fastboot or ADB command you run. Therefore, the above command will look something like this for you:
If your device is detected, you will receive a valid response along with the device ID of your Nexus 6. If not, you will get a timed out error in which case you need to repeat Steps 1-4 mentioned above.
Step 6: Finally, unlock the bootloader of your Nexus 6 by running the following command:
fastboot oem unlock
You will need to confirm the selection on your handset by pressing the Volume Up button. Your device will reboot back into Bootloader mode during the process. Once you get the ‘Device is UNLOCKED’ message on your screen, use the Volume keys to navigate to the Start option and confirm your selection by pressing the Power button.
Your Nexus 6 will now reboot into Android. The first boot, however, boot can take a considerable amount of time so don’t panic.
An unlocked bootloader makes it relatively easy to gain root access or install a custom recovery on the Nexus 6.