[img source : Apple.com]

iPhone 3GS users can now safely update to 3.1 firmware without updating the baseband (for unlock). If you are not the one to download all the various files and just want the ultimate result, these files are waiting for you to download! If you rather want to start from scratch, download Pwnage 3.1.3 tool for Mac.

• Caution #1 : Please proceed further ONLY if you have an iPhone 3GS. iPhone 2G or 3G owners should follow this guide instead.
• Caution #2 : A restore is going to wipe the iPhone clean. Hence, please backup your iPhone using iTunes and then proceed.
• Caution #3 : Don’t install Winterboard just yet. There are some issues that need to be ironed out for 3.1 3GS iPhone.
  

More info about these custom firmware files :

• Has factory boot logos (Apple and restore cable),
• Only Cydia, No Icy,
• 695 MB Root Partition.
  

• The following firmware works only with iPhone 3GS 3.0 or 3.0.1.

• Make sure your iPhone 3GS is Pwned at 3.0 or 3.0.1 (Jailbroken – should have Cydia on it before following the rest of the guide). If not follow these guides first (very important)
  

iPhone 3GS 3.0


iPhone 3GS 3.0.1

• iPhone 3GS 3.1 Out of the Box cannot be unlocked at the moment.
  

Step 2) Join the downloaded files

• The files downloaded above have an extension .001 and .002. They need a special opensource (free) software HJSplit to join.

Download HJSplit to join both the files – Link for Windows Computers here and Macs here.

Step 3) Restore the firmware in iTunes 9.1

• You should now have the respective firmware file with an extension .ipsw . Please follow the steps in order.

Launch iTunes and connect the iPhone to your Mac / Windows computer.

If you are aware of DFU mode, proceed further. If not, watch this quick video and pay close attention to the steps to achieve DFU mode.

Turn your iPhone off. Press and hold the Home button and the Power button at the same time for 10 seconds.

After exactly 10 seconds release the Power button. Continue holding the Home button until iTunes pops up a message saying that it has detected an iPhone in recovery mode.

The iPhone will show you a blank screen (black).

Click on ‘Ok’ to the prompt displayed

For a Mac : Hold Option key and then hit Restore button.

For Windows : Hold the shift key and then hit the restore button.

In the dialog box that pops up, browse the downloaded custom firmware file.

Step 4) Give it few minutes to perform the restore. Once the iPhone is up and running, proceed for software Unlock using Cydia. Follow this guide to install Ultrasn0w to software unlock your iPhone 3GS. iPhone 2G is already unlocked with this custom firmware!

You are now good to go! Post a comment if you are stuck at any of the steps described above.

[Pwnage Tool is developed by the Dev Team. This is just a custom firmware file created using that tool]

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