How to Downgrade your Bootloader with ZiPhone (Windows)

Step by step instructions on how to downgrade your iPhone 4.6 Bootloader to 3.9 with ZiPhone instantly! No downgrading then upgrading!

To do this downgrade you must have restored your iPhone to 1.1.3 and then followed this tutorial to unlock:
http://www.iclarified.com/entry/index.php?enid=666

WARNING: THIS TUTORIAL HAS A HIGH LIKELIHOOD OF BRICKING YOUR IPHONE. ANY TINY MISTAKE OR PROBLEM CAN MEAN A BRICK FOR GOOD!

Why would you still want to do this? The 04.03.13 baseband can be unlocked on 3.9 BL. This means you can have Google Locater working. Also, all old secpacks will not validate on 4.6. The 4.6 Bootloader requires a secpack of a newer version to let you do things with the baseband; whereas, the 3.9 BL requires the same version OR newer.

Perform these steps with your iPhone on and connected to your computer.

Step One
Download ZiPhone from: here

Step Two
Double click ZiPhone.zip on your desktop to extract the folder ZiPhone..

Step Three
Press the Windows key and R at the same time to bring up the Run window. Type in cmd and press the Ok button to launch the Command Prompt.

Step Four
Type the following command into the Command Prompt to navigate to the ZiPhone directory:
cd Desktop/ZiPhone.

Step Four
Execute the command ziphone to see all its possible uses.

Step Five
The program will prompt you to put your iPhone into recovery mode. To do this please hold down both the Sleep/Wake and Power buttons until you see the Apple logo. Once the Apple logo appears release only the Sleep/Wake button until you see the iTunes logo and cable on the screen.

Step Six
If you have a 4.6 BL iPhone you can now downgrade your bootloader! Just simply type in this command:
ziphone -b -v

Step Seven
The program will now search for zibri.dat. Then it will search for the iPhone. Once found it will tell you to wait for 2 minutes and 30 seconds.

Step Eight
After this time your iPhone will reboot and it will be bootloader downgraded to 3.9 with the 04.03.13_G baseband!

NOTE*: After completion its probably a good idea to install BSD Subsystem first then OpenSSH from Installer.app

NOTE*: If you are in an unsupported country YOU MUST patch AppSupport after unlocking or your dialer will keep crashing as will your SMS:
http://www.iclarified.com/entry/index.php?enid=598

THANKS***: Big thanks go to Zibri for creating ZiPhone. You can link to his blog for updates: here

Comments (32)

pradip shrestha - May 29, 2009 at 11:40am

Download application in iphone there is not problem but its could not open

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sudhir - December 11, 2008 at 3:56am

how downgrade baseband 2.1,i have upgrade 2.2 and re downgrade 2.1, now phone is locked , how i downgrade baseband

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wombat - February 28, 2008 at 6:23pm

...using ZiPhone 2.4 it worked just fine. Now I have Bootloader 3.9_M3S2 and Modem Firmware 04.03.13_G. The APP Baseband Info says that I have Mode iPhone 1.1 although I\'m actually on 1.1.3. Guess it\'s the same. Everything works fine so far....... ----------------------------now waiting to upgrade to 1.1.4------------------

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wombat - February 26, 2008 at 6:26pm

@iClarified: Meanwhile we are at ZiPhone GUI V 2.4....................I used the method in the previous tutorial, which did not have the option to downgrade the bootloader from 4.6 to 3.9. Now 1.1.4 is on the market.........My Q.: should those who did not use the option (as not yet available) to downgrade the bootloader in order to get to Firmware 04.03.13_G????? With 1.1.4 out it seems to make more sense now to downgrade to 3.9.....................

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Dg - February 15, 2008 at 10:01pm

There are some answers / help for the questions flying around here on: http://www.hackint0sh.org/forum/showthread.php?t=30238 Worth taking a look.

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steve anderson - February 15, 2008 at 6:41am

iclarified all went well dl to 3.9 but got no sound at all any idea mate

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steve anderson - February 15, 2008 at 6:36am

no souind at all any ideas

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Grzegorz - February 15, 2008 at 3:29am

Thx Russell :)
I did Restore in iTunes (to newest version which is atm 1.1.3)
Then did run ZiPhone 2.1: \"ClickHereX4.6.bat will call Ziphone -b -j -a (Downgrades bootloader be warned, use for iphone > 1.1.2)\"
But somehow iPhone screen was \"Slide to emergency\" aftewards. Only Bootloader downgrade was successful.
So again i run ZiPhone 2.1, now GUI, checked Activation, Jailbreak and Unlock.
In 2\'30\" i had fully working unlocked 1.1.3 phone :)
Sending sms to multiple users works, Google Maps located me on the map with right position, thanks to cellullar towers. So i suppose everything works fine. At last. :)

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John - February 15, 2008 at 2:45am

What happen for those that were the GeoHot early adopters With 4.6 BL ? What happens when we try to downgrade our bootloader?

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Steve anderson - February 15, 2008 at 1:34am

yes I have done b option works fine

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