From the previous UCALC4 firmware leak for the Samsung Galaxy S2 Skyrocket SGH-I727, a new and updated firmware has surfaced. The latest Android 4.0 Ice Cream Sandwich UCLD2 firmware has been revealed and ready to be flashed to your mobile phone.

Developers from RootzWiki have leaked the UCLD2 firmware which can be flashed via Odin3. You can flash the latest ROM without needing to root your phone. But, for those who have a rooted phone, you can also flash the ROM via ClockworkMod Recovery. Senior XDA Developers member yaldak made the updates into a flashable ZIP which you can flash using ClockworkMod Recovery.

So, if you want to update your phone to the latest firmware, continue reading the rest of this guide to learn how to flash Android 4.0 Ice Cream Sandwich UCLD2 firmware to your Samsung Galaxy S2 Skyrocket.

Caution

• The instructions in this guide are intended for use with AT&T’s Samsung Galaxy S2 Skyrocket, model number SGH-I727. Applying these instructions on another device or model may produce undesired outcomes.
• The information in this guide is provided for instructional and educational purposes only. There is no guarantee that these instructions will work under your specific and unique circumstances.
• Use these instructions at your own risk. We shall not hold any responsibility or liability for whatever happens to you or your device arising from your use of the info in this guide.

Requirements

• A Samsung Galaxy S2 Skyrocket SGH-I727
• Backup your mobile data and files before flashing the ROM. You can refer to our guide on how to sync your data to the cloud and how to create local backups of your mobile data.
• Maintain a battery of 60% or more.
• Samsung USB drivers installed. Get them from here and install them to your computer.

Flashing via Odin

1. Download the Android 4.0 Ice Cream Sandwich UCLD2 firmware here (I727UCLD2_OneClick.exe md5sum: 37827a616f222cb1e5f5673315f5f711).
2. Click the I727UCLD2_OneClick.exe to launch Odin on your computer.
3. Switch off your mobile phone.
4. Reboot your Samsung Galaxy S2 Skyrocket I727 into Download Mode. You can do that by doing the following steps:
   • Prepare your USB cable by connecting it to your computer. Do not connect your phone yet.
   • Press and hold the Volume Up key and Volume Down key on your phone simultaneously.
   • While keeping the Volume keys pressed, connect your phone to the computer via USB cable.
   • Keep pressing the Volume keys until Download Mode boots.
5. The word “Added” will be displayed in Odin. This signals that your phone has successfully connected with your computer.
6. Click the Start button to start flashing the UCLD2 firmware to your mobile phone.
7. After installation is complete, the word “Pass” will be displayed on Odin. Your phone will automatically reboot. You can now disconnect your phone from the computer.

Troubleshooting

If Odin or your phone becomes unresponsive in the middle of the flashing procedure, do the following steps:

1. Unplug your phone from the computer and close Odin.
2. Remove the battery and wait for a few seconds.
3. Re-insert the battery to your phone.
4. Repeat the procedures from step 2 onwards.

Flashing via ClockworkMod Recovery

NOTE: You will be needing a rooted Samsung Galaxy S2 Skyrocket with ClockworkMod Recovery (CWM) installed. Check out our guide on how to root your Samsung Galaxy S2 skyrocket. You can also refer to this guide on how to root your phone running Android 4.0.3 UCALC4 firmware. For ClockworkMod Recovery, check this guide on how to flash ClockworkMod Touch Recovery to your phone.

1. Download the following to your computer:
   • Download the CWM-flashable UCLD2 package from here (skyrocket-ucld2-ics-leak.zip, md5sum: 5cb721bcacdadf7de2b0b9f041acc114).
   • Download the root fix file from here (su-bin-3.0.3.2-efghi-signed.zip, 164 kB).
   • Download the Facebook and Samsung keyboard fix here (UCLD2FontHotfix.zip, 226 kB).
2. Copy the skyrocket-ucld2-ics-leak.zip, su-bin-3.0.3.2-efghi-signed.zip, and UCLD2FontHotfix.zip to the root of your phone’s SD card.
3. Switch off your mobile phone.
4. Reboot your phone into ClockworkMod Recovery. To do that, press the Volume Up key, Volume Down key, and Power button simultaneously until Recovery Mode boots. NOTE: Once in Recovery Mode, use the Volume keys to navigate and Power button to select an option.
5. Perform a full wipe by doing the following:
   • Go to Wipe Data/Factory Reset and confirm the action on the next screen.
   • Select Wipe Cache Partition and confirm the action on the next screen.
   • From the main menu, select Advanced. From there, select Wipe Dalvik Cache and confirm the action on the next screen.
   • Go to Mounts and Storage and select Format /system on the next screen. Select Yes on the next screen to begin formatting your system.
6. Go back to the main menu and select Install ZIP from SD Card.  Select Choose ZIP from SD Card and highlight the skyrocket-ucld2-ics-leak.zip. Confirm the action on the next screen to begin flashing the ZIP file to your phone.
7. Repeat step 6 but this time flash su-bin-3.0.3.2-efghi-signed.zip to your phone.  You will meet an error message after flashing this file.  Just ignore the error message.
8.  NOTE: Ignore the error after flashing this file. Just go to Superuser and make an update after booting your phone.
9. Flash the UCLD2FontHotfix.zip file in the same manner as in step 6.
10. After installing the 3 files, go back to the main menu and select Advanced. From there, select Fix Permissions.
11. Go back to the main menu and select Reboot system now to restart your mobile phone.
12. Once your phone has rebooted into Normal Mode, launch the Superuser app and update the su binaries.

Congratulations! You have successfully updated your Samsung Galaxy S2 Skyrocket SGH-I727 to the leaked Android 4.0 Ice Cream Sandwich firmware UCLD2.