Check Fus is a great way to quickly check, without even downloading, the latest official firmware for your region. This is very helpful for knowing what you got shipped, and what version you should download, and flash to get back to stock, in order to send it in for warranty.
This will only DOWNLOAD the ROM, and NOT flash it. To flash it, you will have to use ODIN, and the appropriate way of flashing it (for your phone).
-Here is a guide on returning back to stock on the Samsung Galaxy S GT-I9000
-Here is a guide on returning back to stock on the Samsung Galaxy S III GT-I9300
Here is a written guide:
How to get into:
Download mode: Down + Home + Power keys
CWM Recovery: Up + Home + Power keys
-Download samsung drivers for the S3, via Kies for example
-Download firmware, relevant to you
-Un-Zip firmware and ODIN files -> you will get 2 folders
-Backup anything important, like SMS, contacts, apps etc, and save them to your PC
-Get Triangle Away app
-Use Triangle Away app to get into warning/download mode
-Let Triangle Away reset counter & reboot phone
-After reboot, switch off phone
-Get into download mode, and check if it has successfully reset the counter
-From download mode, go straight into recovery (don’t worry, the phone isn’t downloading anything, and you won’t damage it)
-Wipe data/factory reset, wipe cache, wipe dalvik
-Go into download mode
-Launch Odin, and setup stock rom MD5 file in PDA (do not touch anything else)
-Plug phone in
-Hit start & patiently wait for it to finish
-After phone has booted and you have fully booted up, unplug wire
-Check phone version is correct to what you flashed – in dialler type: *#1234#
-Get you IMEI number (keep this number confidential) by typing in dialler: *#06# – write this number on a piece of paper
-Get into CSC chooser & installer by typing in dialler: *#272*IMEINumber#
->If the CSC is wrong, or not right to your relevant region – Go here and get the right one for you
–>Install relevant CSC if it is wrong
-Wipe INTERNAL SD card, by factory resetting in settings, on your phone.
-Let phone reset, and reboot
-(optional) plug into Kies and let Kies upgrade your phone to the latest firmware
-Turn off phone and get into download mode
-Make sure you have no flash counter registered
-Reboot phone using power key
-Send into Samsung, sell and do as you wish on your “never flashed”, still valid for warranty Samsung Galaxy S III 🙂
On another note, you might be interested to know that, when on a custom ROM, and flashing another custom ROM via CWM, after using triangle away to reset the counter, your counter will not be increased.
For more information, watch this video:
Hope you enjoyed this extensive guide!
Here is a full guide on how to flash back to stock!
In this video I cover:
-JPU – Full ODIN flash
-JPY – PDA Only flash via ODIN – to make it able to connect to Kies
-JVO (latest as of 17/06/11) gingerbread ROM via Kies
Remember to wipe the INT SD and Factory reset before you send it in!
You have to register and once you download the files you will be prompted to enter a password. It is mentioned on http://www.samfirmware.com/ however here are the 2 variations of passwords you will need to extract the file to your PC:
## Password is = samfirmware.com
# Password is = samsung-firmwares.com