1. edwin2213's Avatar
    So I know there are many related threads, but I have not been able to find an answer yet, so I am starting my own. I regrettably upgraded to 3.1.3 on my iPhone 3G. I have modem firmware 05.12.01 and I believe bootrom 5.09. Using my work computer running windows XP SP3 I was able to downgrade to 3.1.2 with service on ATT using the following steps: (Thanks gaetanospqr)

    Originally Posted by gaetanospqr View Post
    I've done it my way~!
    I've finally got my JB back, Iphone 3gs 3.1.3 firm 5.12.01 with official carrier active, after days of working at it, after losing my usb activity and having to restore my vista windows from a recovery disk to get my keyboard and mouse to work not just only in bios. This is not the neatest but just read.

    Here it is for all of you who have the same 3gs setup as me, you must have already had your phone jb and shsh backed up on cydia 3.1.2 or below, now from 3.1.3 you're going to follow the downgrade methods of pointing the host file to cydia as described everywhere~!

    first download quickpwn22 and unzip to a folder or desktop. I'll tell you when to use this, this will get you out of recovery and give you your offical carrier.

    Down grade to a downloaded custom 3.1.2 ipsw, open itunes plug your phone in and put your phone in dfu mode not recovery mode, hold sleep and home 10 seconds let go sleep and contiue to hold home 10 seconds till a pop up on itunes tells you you're in recovery mode and need to restore in order to continue,

    hold shift and click restore same time navigate to custom 3.1.2 ipsw file and restore when it's done you will get an error 1015 or 1014, that's ok that means you're backed up on cydia and it's communicating, the you will be in recovery mode where you will see disk and connection cord on screen, just click shift and restore and insert custom ipsw file again hit restore.

    same error message 1015 will appear, now start quickpwn 22 while your still jacked in on itunes, it will give you a message that says hold sleep and home for 15sec then let go of home and continue to hold sleep for 2 seconds, this will get you out of recovery and your official carrier back, next run latest rc3 blackra1n jb, and it's done~! downgraded to 3.1.2 with firmware 5.12.01 and official carrier with jb~!

    My problem is that I would like to sync my iPhone 3g back to my personal computer (27 inch i5 iMac running 10.6.3) As I understand it,to do this I have to wipe my phone. However the steps that worked perfectly with Windows XP do not work with Mac OS X. Does anyone have a guide to downgrade a 3G on OS X? I have seen a couple but they require some terminal use, which I do not have that much experience in. Is there a way to link a Windows formatted iPhone to Mac OS X?

    Sorry for the long winded post and thanks for your help!

    - David
    2010-04-22 07:12 PM
  2. Prox's Avatar
    Google is your friend/answer.
    "I want to change the world but they won't give me the source code"

    "With Great Power , Comes Great responsibility" That is something we all need to remember

    2010-04-23 06:19 PM
  3. Simtech's Avatar
    any restore will wipe your phone. you will have to resync after restoring.
    2010-04-23 06:23 PM