Downgrade Baseband 5.15.04 to 5.13.04 then Unlock with ultrasn0w (3G Only) |

Downgrade Baseband 5.15.04 to 5.13.04 then Unlock with ultrasn0w (3G Only)

February 14th, 2011 81 Comments

This method will only work for iPhone 3G with bootloader version 5.08 (5.8)!

UPDATE: If you have an AT&T iPhone 3G/3GS, unlock it permanently using this.

You can quickly check your bootloader version by using TinyUmbrella. Download it from here. It should show your bootloader version right away.

Alternatively, you can also try using f0recast [Windows or Mac]. If you have bootloader 5.8, you will see the prompt below:

Lets start!

What you need:

  1. Jailbroken iPhone 3G
  2. Fuzzyband – install this from Cydia
  3. afc2add – install this from Cydia although not necessary
  4. i-Funbox – a file explorer for iPhone, Mac users can use DiskAid
  5. 5.15.04 certificate (download ICE2-05.15.04.cert) for Fuzzyband


  1. Launch Fuzzyband after installing the app via Cydia.
  2. Connect your iPhone to the computer.
  3. Launch i-FunBox and select File, then go to Applications/, right-click and then select Copy from PC.
  4. Copy ICE2-05.15.04.cert you have downloaded earlier to this location
  5. Go back to Fuzzyband and you can now begin the downgrade process. If the downgrade is successful, you should see “I Haz Downgrade
  6. You can now unlock it with ultrasn0w.
Related Posts Plugin for WordPress, Blogger...

Richard Ker

An IT specialist by day and an iPhone hardware repair specialist by night. Enjoys iPhone jailbreaking, unlocking and hardware hacks.

Website - More Posts

unlock iOS 6.1.3  

Sign up Free Email Newsletter

Stay Updates with this Blog. Get Free email newsletter updates, Enter your Email here:

Don't forget to confirm your email subcription


81 Comments to “Downgrade Baseband 5.15.04 to 5.13.04 then Unlock with ultrasn0w (3G Only)”

  1. egiron says:

    Excellent! It really works for me. But several weeks ago I had tried with ICE2-06.15.00.cert with no success (Step 4) but later I read again and downloaded ICE2-05.15.04.cert and voila! it works like a charm… Thanks for your post…

  2. Piyush says:

    Do u have anything fot bb 2.10.04?

  3. Praveen Madhu says:

    Thanks very much man……………………..

    It's Really worked me

  4. Michele says:

    Hi guys.
    I did it this morning.
    Everything well fine, but after that process I've rebooted the phone and now it doesn't switch on… It stay on the apple logo…

  5. [...] sarebbe un modo al momento per fare il downgrade: Downgrade Baseband 5.15.04 to 5.13.04 & unlock with ultrasn0w 1.2 | Io ho quel bootloader, quindi l'ho provato… ho seguito tutta la procedura, poi ho riavviato… ed [...]

  6. bononoy says:

    hi. do you have by any chance a procedure for bootloader 5.09 Iphone 3G? need to unlock my phone. thanks!

  7. iphonerepair says:

    have you tried updating to baseband 6.15?

  8. bononoy says:

    i cant upgrade it to 6.15. for some reason redsnow does not recognize it when i follow the onscreen instruction. any tip?

  9. bononoy says:

    i was able to finally upgrade it to 6.15 using Redsn0w but my wifi stopped working. i have 4.2.1 IOS. I was able to unlock however using DiskAid method (no WIFI needed) but I need WIFI connectivity on my Iphone 3G. Help, pls!

  10. bononoy says:

    i was able to upgrade it to 6.15 but went back to 3.1.3 due to issues I encountered in 4.2.1

    now my wifi is still not working even when I was on 4.2.1 bb 6.15. pls help.

  11. bononoy says:

    what exactly do you mean by flashing the baseband using redsn0w?

  12. bononoy says:

    it is now on 6.15.00 but stil wifi is not working. can't identify any wifi connection at all. hope there is a solution to this.

  13. bononoy says:

    it only stopped working after jailbreaking. :(

  14. Venu says:

    this works perfectly

  15. Michael says:

    if you're downloading from 5.15.04 to 5.13.04, why use 6.15.00 certificate?

  16. lovelife says:

    what about 5.15.04 with bootloader 6.4? – any luck ?

  17. dinesh says:

    what about 5.15.04 with bootloader 5.9

  18. venk1120 says:

    Works like a charm iOS 4.2.1, iPhone 3G, Bootroom 5.08 — downgraded baseband and managed to unlock !!! A+++++

    just follow the instructions !!!

    • ozknowhow says:

      i have the same problem, with bootload 5.9 :-(
      could you please send me an email in case the one for 5.9 coming out? thanks.

  19. Rob says:

    I upgraded my 3G to 4.2.1.I lost Wifi and the SIM is locked again. How can I install Fuzzyband if I have no connection ?

    Please help !?

  20. Purehate says:

    I upgraded my iPhone 3G from iTunes by mistake

    Now I have Baseband 5.15.04

    Bootloader 6.2_M3S2

    How can I downgrade it ?

    I have iOS 4.2.1 (Jailed)

    I m ruined help me …

    help me !

  21. Tom Toon says:

    I have the same problem as you @Purehate.
    I upgraded by Itunes by mistake.. and now i have a useless phone.
    If anybody finds or knows any Downgrading software for bootloader 6.04 then please message me In desperate need.

  22. Carlos G says:

    este tutorial funciona perfecto, claro con las condiciones que menciona, un iphone 3g con 3.1.3 y boot 5.08 con base en 5.15.04 y el fuzzy lo modificas y te baja la base y ya lo puedes liberar con ultrasnow, perfect, gracias.

  23. McDali says:

    Dude!!! it works! Just Great.. thks :D

  24. dee says:

    Hi, I have BL 05.09 and BB 05.15.04 with iOS 4.2.1 on my 3G.

    Seems like I can’t use this steps on my phone.

    is it the BL is not supported?

  25. That guy says:

    Worked great, thanks.

  26. Saurax says:

    I have Baseband 5.15.04

    Bootloader 6.2 M3S2

    I have iOS 4.2.1

    Want to Jailbreak & unlock it, any help??


  27. [...] đã làm theo ở đây và downgrade thành công xuống bản 05.13.04. Mọi người vào tham khảo nhé, vãi ngu [...]

  28. Thank a lot.
    have good day :) .

  29. I'm copy ICE2-05.15.04.cert to Applications/ and then downgrade, after iphone reboot, version BB not show and wifi not connected,.
    What about now?

  30. My iphone BB 05.15.04 iOS 3.1.3 and boot loader 05.08. Plz help me ^^.

  31. Dude2001 says:

    This worked like a charm, now on 4.2.1 and running baseband 5.13.03

  32. nuclear_84 says:

    Great Help Thanks :)

  33. Carlos says:

    Please help me!
    I have Iphone 3G, booloader 5.8, baseband 05.15.04 and iOS 3.1.2, but i can´t do this!

    When i open Fuzzyband appears a message:
    "Downgrading ICE2-05.15.04 is not supported at this time"

    Please tell me what´s the problem, because if this guide is for 05.15.04 why fuzzyband says is not supported!

  34. Nancy Botwin says:

    DID NOT WORK! and paid $10 for the software. Thanks for nothing

  35. dol says:

    work like charm….thanks

  36. Spidertak says:

    thanks man you are the one

  37. George says:

    for those whose bootloader is 5.9 and above – have any of you tried a SIM card hardware unlock method such as the Gevey SIM adapter? Does it work?

  38. bob says:

    yeh man it work for me too

  39. Rohan says:

    Hey I have iPhone 3G wit os 4.2.1 n bb 5.15.04 n my bootloader version is 5.09 when I lunch fuzzy band it says not supported

  40. Ali says:

    Thanks dud.

  41. Giggs says:

    it worked. Had to download the the ifunbox from the offcial page

    and the certificate from this link…

    , but in the end I got the magic message "I Haz Downgrade" and have now unlocked the sim.

    thanks for the help

  42. Joey says:

    i have done everything it says to but everytime i open fuzzyband it say "querying modem" then closes.
    HELP !!!
    it for my dad

  43. tunde says:

    guys pls how can i upload boostloader on ma 3g 16 gg. am having problem wit ma baseband.

  44. Bill Riemers says:

    Your instructions didn’t work at all for me. It turns out redsn0w doesn’t work correctly with iTunes 10.6. Neither does f0rcast. Tiny Umbrella works, but did not show my bootloader version. I finally went with the following instead:

    1. Restore to 4.2.1

    2. Download redsn0w 0.9.6rc19 and the 4.2.1 ipsw file.

    2. Run redsn0w 0.96rc19.

    3. Select the IPSW for 4.2.1 I had already downloaded.

    4. Install cynthia to jailbreak.

    5. Use cynthia to install fuzzyband.

    6. Run fuzzyband.

    At that point I stopped, as fuzzyband reported I have bootloader 05.09.

    So since I couldn’t downgrade, preceeded with the upgrade.

    7. Download redsn0w 0.99.10b6.

    8. Download itunesMobileDevice.dll

    9. Copy itunesMobileDevice.dll to the redsn0w 0.9.10b6 directory.

    10. Rename itunesMobileDevice.dll to MobileDevice.dll.

    11. Run redsn0w 0.99.10b6

    12. Select the ipsw file.

    13. Jailbreak. Uncheck the install Cynthia and battery checkboxes. And check the ipad baseband checkbox.

    14. Once jailbroken install ultrasn0w with cynthia and reboot.

    Of course the problem with upgrading is it is one way only, and for some people the GPS doesn’t work afterwards. For me the GPS is working fine, but I notice there are no longer any location services settings. So my guess is if you upgrade with your GPS turned off, it will remain off forever. If you upgrade with your GPS turned on, and you are lucky it will remain on forever.

    For those trying different versions of redsn0w here is what I found with iTunes 10.6 instealled. 0.99.10b6 will give an an allocate (233) error if you try to install cynthia. The earlier versions of 0.99.10b* will not recognize the iPhone as connected in DSU mode. Consequently this is why I ended up using 0.96rc19 for the initial breaking.

    As I commented above f0rcast is broken and tiny umbella are useless. However, even if they worked it seems like a redundant extra step since fuzzyband will report the bootloader version.

  45. Bill Riemers says:

    Oh excuse me, my comments should have been posted on the page that referenced this page, as that is the page that gave the parts of the instruction that didn’t work.

  46. Oyunaa says:

    pls, help mr. after downgradind there has no wi fi .

  47. vogel says:

    nice tuto thx you

  48. john says:


  49. agnaldo says:


  50. Kuty says:

    Thanks man you saved my phone…!
    That works perfectly…!

  51. adictango says:

    Hoy realize este proceso agragando el certificado del 05.15.04 y me funcino a la perfeccion al primer intento y me paso al 05.13.04 y mi telefono funciona a la perfeccion

Leave your comment here:

unlock iOS 6.1.3

Enter your email address:

Delivered by FeedBurner