blue sky service center: Sony Ericsson Xperia Arc S LT18i: Root, bootloader unlock, and custom recovery

Thursday, August 16, 2012

Sony Ericsson Xperia Arc S LT18i: Root, bootloader unlock, and custom recovery

by Carl Parker on Apr 20, 2012 with 21 Comments

With how much information the Internet is packing, finding methods to root one’s phone and to install custom recovery is no problem. What is a little more difficult, however, is finding all that information in one spot.
For that very reason, we’ve compiled some methods on rooting and installing custom recovery on your Sony Ericsson Xperia Arc S. You won’t need to swim through tons of Google search items or juggle dozens of tabs. Everything you’ll need for your phone is right here.

Caution

Take note that the methods below for rooting and installing custom recovery is compatible only for the Sony Ericsson Xperia Arc S, model number LT18i. You may check your device’s model number through Settings > About Phone. If your device does not match the Sony Ericsson Xperia Arc S, model number LT18i, we highly discourage you from attempting to use these methods as it may lead to bricking.
Use these instructions at your own risk. We shall not be responsible for damage or any undesired outcome arising from your use of these instructions.

Requirements

If you’re excited to root your device and to install custom recovery on your Xperia Arc S, you’ll need the following:

Make sure to create a backup of any important data on your Xperia Arc S as data may be lost or corrupted during the rooting, unlocking bootloader and install custom recovery processes. You may check our guides on how to create a local backup of your data andhow to backup your data to the cloud.
Make sure that you’ve installed the ADB drivers for your phone on your computer.
Enable USB Debugging on your Xperia Arc S. You can do this through Settings > Applications > Debugging > USB Debugging.
Enable Unknown Sources. You can do this through Settings > Applications > Unknown Sources.

Rooting

Rooting 4.1.A.0.562 (stock ICS firmware)

This Windows-only method works for both locked and unlocked bootloaders. Not only does it root your device using the Android emulator trick but it also installs Busybox (1.18.4) and installs ICS-specific SU files.

Make sure that your Xperia Arc S is running on stock ICS firmware 4.1.A.0.562.
Download DooMLoRD_v1_Xperia-2011-ICS-ROOT-emu-busybox-su.zip (md5sum: dc7f4a107e7d991572219404a9ca996e) and save it on C:\ of your computer.
Extract the contents of the zip file using 7-Zip, WinRAR, or other similar file extraction programs.
Connect your Xperia Arc S to your computer via the USB Cable.
Double click on the runme.bat file.
Follow the instructions on screen.

Your Xperia Arc S will reboot a couple of times. When the script finishes rooting your phone, it will say “ALL DONE.” Enjoy your rooted device!

Rooting 4.0.2.A.0.62 (stock Android 2.3.4 firmware)

Rooting an Xperia Arc S running on 4.0.2.A.0.62 is a little more complicated, as it requires you to downgrade your firmware first to stock firmware 4.0.2.A.0.42 using a Generic Global, and not region specific firmware.

Downgrade to stock firmware 4.0.2.A.0.42 Generic Global.
1. Download the LT18i 4.0.2.A.0.42 Generic Global FTF (Xperia Arc (LT18i)_4.0.2.A.0.42_CE.rar, size: 155.17 MB).
2. Download Flashtool 0.6.9.1 to your computer and install it according to these instructions.
  - For Windows users (MD5: 9E6AEAA286FC145FDEBD65F6CC492585):Mirror 1 | Mirror 2
  - For Linux users (MD5: 0BB12562F21B5291F34CD06272EB10F5): Mirror 1 |Mirror 2
3. Before you continue, you’ll need to disable your computer’s antivirus software as it interrupts the tool.
4. Flash the LT18i 4.0.2.A.0.42 Generic Global FTF using Flashtool 0.6.9.1.
Root the phone using DooMLoRD’s Easy Rooting Toolkit.
1. Download DooMLoRD’s Easy Rooting Toolkit (DooMLoRD_v4_ROOT-zergRush-busybox-su.zip) to your computer.
2. Extract the file using 7-Zip, WinRAR, or other similar file extraction programs.
3. Extracting the file should give you the runme.bat file.
4. Connect your Xperia Arc S to your computer via the USB cable.
5. On your computer, double click on the runme.bat file to launch it.
6. Follow the instructions on the screen.
Perform OTA upgrade for 4.0.2.A.0.62.
- Do not use the PC Companion to upgrade back to firmware 4.0.2.A.0.62, otherwise root will be lost.

Your Xperia Arc S should now be rooted. You can now continue to installing ClockworkMod Recovery on your Xperia Arc S.

ClockworkMod Recovery

Thanks to pvyParts and nobodyAtall, both recognized developers on XDA Developers, it is now possible to easily install ClockworkMod Recovery 5 on your Xperia Arc S. The Xperia Auto-CWM Installer app appears to be working for both locked and unlocked bootloaders. Download theXperia Auto-CWM Installer from the Google Play Store and easily install ClockworkMod Recovery on your Xperia Arc S without the hassle of wires or command prompts. The app, however, requires your Xperia Arc S to be rooted and to be running on stock 2.3 software.
If you’d like to read more about the app, we recently wrote an app review for the Xperia Auto-CWM Installer.
Once you’ve installed Xperia Auto-CWM Installer, you’ll see a checklist that shows you the app’s requirements for installing ClockworkMod Recovery. If you’ve accomplished all of the app’s requirements, simply tap Install CWM 5 from the menu.