How to Make Clean Installation of CM12 ROM on OnePlus One

If you are the Oneplus one user and most of the time you are installing the custom ROM or Cyanogenmod CM 12 Android 5 ROM on your device. But most of the time when you are installing Custom ROMs on your phone, you are facing some problem like bad battery performance, or some other problems. At that time it was recommended to do a clean installation of the ROM on your phone. This will help you to improve the performance of your device. Today in this guide we’ll show you how to do a clean installation of CM 12 ROM on One plus one, you can also use this guide with some other custom ROM or with the Stock ROM fastboot zip file. The guide is pretty simple and take some time to complete the process.

To get started you need a OTG Cable with USB drive or OTG USB Drive, CM 12 Rom Zip file, Google app zip package. Yes this guide is only for those user who already unlocked the bootloader of the phone and running the TWRP recovery on the phone. Before following this guide do take the full backup of your phone, you will lose all your data, messages and contacts.

Make Clean Installation of CM12 ROM on OnePlus One

Read Also: Root, Unroot, Unlock, Restore OnePlus One with Wugfresh ToolKit
Read Also: Restore OnePlus One to Stock Firmware With OnePlusRecovery Tool(Fixes Brick too)

Instruction to Clean Install CM 12 on OnePlus

Step 1. First unlock the bootloader of Oneplus and Install latest TWRP recovery from here.

Step 2. Now download the OnePlus One CM 12 Nightlies here and Download the Gapps package here and move the both zip file to the OTG USB Drive.

Step 3. Now switch off your Oneplus android and boot it in recovery mode. You can do this on your OPO by holding both the volume down and power buttons.

Step 4. In TWRP recovery mode do the following:

-Wipe data
-Wipe cache
-Wipe Dalvik cache
-Wipe Internal storage
-Wipe System
-Format data

TWRP Wipe Cache and Data System

So after that, no OS is installed.

Step 5. After that Reboot to recovery.

Step 6. In recovery mode:

-Connect the USB Flash through OTG cable
-Go to Mount and tick the OTG
-Go Back and Browse the USB drive. (To find it, go to the root destination after pressing Install Zip and select the folder /usb_otg that is your USB Flash)
-Select Install zip and Flash the CM 12 ROm Package first and after that Flash the Google apps package on your phone.

Step 7. Now Reboot the system from recovery main menu and the first boot will take some time.

Step 8. After the first boot, turned off the device and reboot to recovery mode again.

Step 9. Then:

-Wipe data
-Wipe Cache
-Wipe Dalvik Cache
-Wipe Internal storage
-Format data

Don’t select the system option this time, otherwise you will lose the OS again.

Step 10. Then reboot and after the device’s boot let phone 3-5 minutes to settle or go straight if you can’t wait to:

-Backup and Reset
-Untick the 2 boxes
-Reset device

Let the phone boot up and settle its first background processes 3-5 minutes and you are ready. Now you phone has the CM 12 ROM with Clean installation. Enjoy!