iPhone Dev team have also added a feature called DFU IPSW that should make it a lot easier to put an iOS device in DFU mode.
The DFU feature will be extremely useful for users who can’t put their iOS device in DFU mode due to a faulty or non-responsive Home or Power button.
This version of Redsn0w covers 3 different types of NOR chips in the iPhone 3G and iPhone 3GS (the earlier version covered only the most prevalent NOR chip), so iPhone 3GS users who had problems downgrading the baseband using Redsn0w 0.9.14b1 should try this version of Redsn0w as it should fix their issue. The previous version covered only the most prevalent NOR chip.
iPhone 3GS and iPhone 3G users can follow these simple steps to downgrade from 06:15:00 baseband:
- Connect your iPhone in normal mode, then click “Jailbreak” after redsn0w identifies its model and BB version (you needn’t pre-select the IPSW anymore).
- Choose the “Downgrade from iPad baseband” option (you needn’t worry about de-selecting Cydia anymore).
- Do a controlled “slide to power off” shutdown of your phone and proceed through the normal DFU ramdisk steps.
Dev team have again reiterated that iPhone 3GS units manufactured in early 2011 or later have a NOR chip that’s incompatible with 06.15.00 and so trying to install the iPad baseband will brick the device.
For those who are wondering if you can update your 3G or 3GS to 06.15 solely for the purposes of downgrading to 05.13.04, the answer is “yes” for 3G owners, and “maybe” for 3GS owners. The iPad baseband is not compatible with 3GS units manufactured week 34 of 2011 or later. If you have an iPhone3GS and if digits 3-5 of its Serial Number are 134 or later (xx134…), then you should NOT try to install the 06.15 baseband on your 3GS! It will brick your radio, preventing both the downgrade from working and normal iPhone software from using it as a phone! Be warned!
iPhone Dev team have provided the following details about how to use the DFU feature:
In redsn0w, go to “Extras->Even More>DFU IPSW” and select an IPSW that is currently being signed for your device and that you’d normally be able to restore to without any hacks. redsn0w will create an “ENTER_DFU_” version of the IPSW that you can restore to just like any other IPSW, except that now you’ll be dumped into DFU mode towards the end of the restore (WARNING, your screen will remain completely black…the only way to even know its on is that iTunes and redsn0w will detect it!).
You can download Redsn0w 0.9.14b2 from this link.
Let us know if you were able to successfully downgrade the baseband with Redsn0w 0.9.14b2 in the comments below.