The following step-by-step tutorial/guide will help you unlock your iPhone 3G and iPhone 3GS with the latest iPhone 3.1.2 firmware using ultrasn0w. This unlocking guide applies to iPhone 3G and 3GS only. iPhone 2G users can simply follow the guide I posted here to jailbreak and unlock with firmware 3.1.2.
Note: This unlocking guide will work for you only if your Modem Firmware (Baseband) version is 04.26.08. If you have upgraded directly to iPhone 3.1.2 stock firmware from iTunes then you are pretty much out of luck for now.
UPDATE: ultrasn0w 0.92 is now available which fixes the missing carrier logo/name on unlocked iPhone 3.1.2 firmware. For more info, follow the guide posted here.
Step 1:Download and install the latest version ofiTunes if you haven’t already.
How to: Jailbreak iPhone on 3.1.2: Step 2: Follow the guide hereto jailbreak your iPhone 3G or 3GS using PwnageTool on firmware 3.1.2.
Step 3:Once you are done with the jailbreak, you can now unlock your iPhone running jailbroken firmware 3.1.2 by using ultrasn0w 0.9. To do this:
Note: T-Mobile users should disable 3G before installing ultrasn0w.
Start“Cydia”on your iPhone.
Touch on“Manage”tab on the bottom.
Now touch on“Sources”as seen in the screenshot below:
Touch on“Edit”and then on“Add”. You will be prompted to enter a url source as seen in the screenshot below. Type“http://repo666.ultrasn0w.com”and touch on“Add Source”.
Cydia will now automatically update your sources by following a series of automated steps.
After installation is completed. Search for “ultrasn0w” in Cydia and install this application. This app will automatically unlock your iPhone so that you can use it with any carrier.
Step 4:Now simply restart your iPhone. Voila! You are now running a fully unlocked and jailbroken iPhone firmware 3.1.2 on your iPhone 3G or 3GS.
UPDATE 1: Follow the step-by-step guide posted here to fix missing carrier name or logo on your unlocked and jailbroken iPhone 3G/3GS running firmware 3.1.2.