If you tried to change CSC by using cscselector app or terminal, you will not see any changes and the CSC will stuck in the default code.
I will show you how to change it easily
- Rooted galaxy S4 or any galaxy device.
- Installed root file explorer ES File Explorer or Root Explorer.
- Installed CSCSelector or Terminal app
- Open ES File Explorer or Root Explorer and mount RW.
- Navigate to : System / csc / BTU / system / csc /
- Copy all the files on csc folder and go back to paste it in : System / csc /
- Accept Overwriting or replacing files.
- Use CSC selector app or Terminal method to change CSC to BTU.
- WARNING : Changing CSC will delete all data on your device.
- This method will work only on ROOTED devices
- This will only work if your current firmware support Multi-CSC
- It might display "PreconfigUI does not support SingleCSC" if your current firmware doesn't support Multi-CSC.
- This method should work for many galaxy devices which running Android jelly bean and KitKat.