How To Downgrade iPhone3GS 6.15 Baseband Using Redsn0w
The iPhone Dev-Team as promised has released an updated version of redsn0w that will allow iPhone3GS and iPhone3G users to downgrade their device's iPad baseband 6.15 which was performed in order to unlock the devices. This however casued certain unexpected issues like battery drainage and loss of GPS in iPhone3GS. It was mandatory to flash iPad's 6.15 baseband on iPhone3G and 3GS as that was the only unlockable baseband that could be unlocked using iPhone Dev-Team's Ultrasn0w unlock. Musclenerd made an announcement earlier that a tool will be released in future that would allow the possibility of downgrading iPhone3GS and 3G basebands to an unlock-able version.
Having said that, today the iPhone Dev-Team proudly announced the release of updated Redsn0w that allows the users to downgrade their basebands. Since playing with basebands is not cool, we decided to prepare an easy to follow instructions guide to downgrade 6.15 baseband.
Update 2 : Happy Independence Day - New Updated Redsn0w Releasing Today
Steps To Downgrade iPhone3GS & 3G 6.15 Baseband
Step 1 : Download the latest version of Redsn0w and the current firmware of your device
Step 2 : Extract the contents of the Redsn0w archive that you just downloaded.
Step 3 : Connect your iPhone3GS or 3G and Launch Redsn0w.
(Windows7 users should select the option of running as administrator by right clicking on redsn0w application and then selecting the option - Run as administrator)
Step 4 : In the redsn0w, go to extras menu
Step 5 : From the extras menu, select 'Select IPSW' option
Step 6 : Navigate to the folder where you download the current firmware of your device and select the firmware and click open.
Step 7 : Click Ok to confirm the firmware selection
Step 8 : Select 'Yes' if your iPhone3GS is newer model or else select 'No'
Put your device into DFU mode
Step 9 : Now go back to the main menu and select the option 'Jailbreak'
Step 10 : The jailbreak process will begin and then Redsn0w will show more options where you need to select 'Downgrade From iPad Baseband' and then click next.
Step 11 : Put your device into DFU mode
- Power off the device completely
- Hold power button for 3 seconds
- without releasing the power button, press and hold home button for 10 seconds.
- Now release the power button and continue holding the home button .
Redsn0w will use limera1n to exploit your device to enter into pwndfu mode. Once done, continue with the steps. Redsn0w will now start processing your device's build
Step 13 : Your device should show some scrolling text and then you should be able to see the pineapple logo indicating 'Flashing Baseband (don't interrupt). Its serious, don't unplug or do anything stupid or you'll never be able to use your device again.
Step 14 : Once done, your iPhone will reboot and you should have 5.13.04 baseband.
If you have any questions or facing any issues, post them in the comments section
Update 1 : Baseband Downgrade Troubleshooting Guide
Update 2 : Revised Steps For Successful Baseband Downgrade
Step 1 : Use iTunes to restore stock Apple iOS 5.1.1 (9B206) IPSW.
Step 2 : Run Redsn0w 0.9.14b1.
Step 3 : Select Clear Cache from "Extra's > Even More" page.
Step 4 : Select IPSW from "Extras" page and select the location of your iOS 5.1.1 (9B206) IPSW.
Step 5 : Power Down the iPhone (slide to power off).
Step 6 : Click Jailbreak and tick only the "Install Cydia" option.
Step 7 : Enter DFU mode and allow Redsn0w 0.9.14b1 to Jailbreak your iPhone and install Cydia.
Step 8 : Re-Run Redsn0w 0.9.14b1.
Step 9 : Select Clear Cache from "Extra's > Even More" page.
Step 10 : Select IPSW from "Extras" page and select the location of your iOS 5.1.1 (9B206) IPSW.
Step 11 : Power Down the iPhone (slide to power off).
Step 12 : Click Jailbreak and tick only the "Install iPad baseband" option.
Step 13 : Enter DFU mode and allow Redsn0w 0.9.14b1 to install the iPad baseband.
Step 14 : When the iPhone reboots, either restore from iTunes backup or create a new phone to get access to Home screen and Apps.
Step 15 : Run Cydia, wait for it to update and then install Ultrasn0w.
Step 16 : Make sure the iPhone is activated and working with iPad baseband, e.g. make a test call.
Step 17 : Re-Run Redsn0w 0.9.14b1.
Step 18 : Select Clear Cache from "Extra's > Even More" page.
Step 19 : Select IPSW from "Extras" page and select the location of your iOS 5.1.1 (9B206) IPSW.
Step 20 : Power Down the iPhone (slide to power off).
Step 21 : Click Jailbreak and tick only the "Downgrade from iPad baseband" option.
Step 22 : Enter DFU mode and allow Redsn0w 0.9.14b1 to downgrade your iPhone baseband.
Update 1 : Musclenerd Confirms iPhone3GS 6.15 Baseband Downgrade - Redsn0w To Be Updated Soon