In this iPhone Guide, you will learn how to downgrade Baseband 2.30 to 2.28 for your iPhone 3Gs having Bootloader 5.8. After downgrading the Baseband you will be able to Unlock iPhone 3G with YellowSn0w. Gurus are working on a similar exploit for higher Bootloader versions.
- Make sure your iPhone Bootloader version is 5.8.
- Make sure that your iPhone 3G is on Baseband 2.30
- You need MobileTerminal to proceed into this guide.
- Mobile Terminal (available under Terminal Support section in Cydia)
Launch Cydia from your iPhone Springboard.
then Go to Sections Tab at the bottom of the screen.
Go to iClarified from the list of Sections. If you’re unable to find it then you need to add following source to Cydia:
Learn how to add Source to Cydia.
From the list of packages, select DownBB.
then Press the Install button at the top right of the screen.
Press the Confirm button to begin installation.
On completion of the Installation, Press the big Return to Cydia button.
Press the Home button to return to SpringBoard and Launch the Terminal.
Input su into the terminal window.
When asked input alpine as password
Input DownBB into the terminal window to launch the Baseband downgrade script.
Now you will be asked to confirm you would like to continue. If you’re sure that you’re on Bootloader 5.8 and Baseband 2.28 input Yes into the window.
DownBB script will be executed to downgrade iPhone Baseband.
When all done, your iPhone will Reboot automatically.
Please note you will now be on the 2.28 baseband.
As you have downgraded iPhone 3G baseband 2.30 to 2.28 now you can unlock your iPhone 3G.
Many thanks to EvilPenguin|, pH, and DHowett for their work on this script! Thanks to Geo-hot for discovering the exploit!