Last year the iPhone Dev Team gave the option to upgrade to the iPad basaband 06.15.00 to unlock the iPhone 3G and iPhone 3GS. The baseband isn’t a very big loss for the iPhone 3G users as Apple discontinued their support to the phone after iOS 4.1 where iPhone 3GS is still in the list of devices getting the iOS 6 update and it very good news for the 3GS users.
Steps to Downgrade for iPhone 3G & 3GS from baseband 06.15.00 to 05.13.04
- Download the Latest Version of Redsn0w for MAC/ Windows computers.
- Unzip the File and Save it on your Desktop
- Download the ExactIPSW of the Version of iOS you are running your phone, you can check it by going to Settings > General > About > Version. You can find the IPSW file by Googling for it or you can just post in the comments below what iOS version iPSW you want and we provide you with the links. Save it in the Same location as the Redsn0w file you downloaded and unzipped earlier.
- Connect your phone to your computer, close iTunes if it opens and then Switch of the phone.
- Now Launch the Redsn0w file and click on the Extras button.
- Then Click on Select IPSW option and browse selece the IPSW file you have downloaded.
- Now the Redsn0w software will ask you if you are running the older bootrom or the newer one, read and Follow the instructions very carefully as of you do it wrong you may end up doing more harm than good (like bricking the phone) so be very careful.
- Now go back to the main screen and select the Jailbreak option, it will take some time and prepare your phone for Jailbreak and will present you with some options.
- Select the options that says Downgrade from iPad baseband and Install Cydia options and thev click Next.
- Follow the on screen instruction to put your phone in DFU mode or Follow the steps given in this link
- After you properly put your phone in DFU mode, the Redsn0w software will take it from there and your phone should be ready with baseband 05.13.04
- After the Jailbreak is complete and your phone has properly booted, setup up Wi-fi connectivity on your phone, disable 3G and then install Ultrasn0w by following the Instruction given here.