How to Jailbreak iPhone 4.3 Firmware

iOS 4.3 Arrives

The long awaited iOS 4.3 is finally out. Yes, you heard me right. Many iPhone, iPad and iPod Touch users have been waiting to see the new iOS 4.3, which was finally showcased by Apple on March 3, 2011. This piece of news is more important for iPhone 4 users as they have been waiting for the new version to be out, so that they get to jailbreak their iPhone which has been stuck on 4.2.1 Firmware.

Apple has released iOS 4.3 GM (Gold Master), accessible only to developers who are enrolled to Apple’s standard or enterprise level program, which means you need to spend a minimum of $99 in order to get access to the new firmware. However, considering the interest of my readers, I have made every effort to provide the information without my readers spending a single penny. In this article, I will guide you on how to Jailbreak iOS 4.3 on iPhone 4. Before proceeding further, make sure you read all the instructions carefully.

NOTE: The steps mentioned in the article are meant to be performed by advanced and expert users only. If you damage your iPhone during the process, neither the website nor the author shall be held responsible for the loss.

Important: This tutorial is applicable only to iPad, iPod Touch 3G/4G, iPhone 4 (GSM) and iPhone 3GS users running MAC OS X.

Step by Step, Instructions

Step 1: Before you Jailbreak iOS 4.3 on iPhone 4, you need to have the following:

Make sure to download and place all the files on your desktop under “iPhoneData”.

Step 2: After you have downloaded all the above mentioned files, unzip the Pwnage Tool Bundle for iPhone 4.

Now, right click on the PwnageTool 4.2 and click “Show Package Contents”. This will open up PwnageTool 4.2 package. Move to Contents, then Resources and then, FirmwareBundles.

Pwnage Tool 4.2

Navigate inside the Pwnage Tool Bundle for iPhone 4 and locate “iPhone3,1_4.3_8F190.bundle”. Copy this package to the FirmwareBundles folder (the folder you located above).

Pwnage Bundle for iPhone 4

Step 3: This step involves installing RamDisk, which will be used for creating a custom Ramdisk for iPhone 4. Perform this step carefully. Double Click the Universal Ramdisk fixer package to install it. Continue to press the “Continue” button, until you see a message that says, “The Installation was successful”.


Step 4: Launch Pwnage Tool 4.2 and click Expert mode on the top. Now, select your iPhone 4 device from the application screen. The left iPhone on the app screen is the correct device. If you are not taken to the next screen, click the right arrow located on the bottom right corner of Pwnage Tool 4.2 application screen.

Jailbreak iPhone 4.3

Now, click on “Browser for ipsw” icon and select the iOS 4.3 ipsw file that you downloaded earlier. If you are not taken to the next screen, click the right arrow located on the bottom right corner of Pwnage Tool 4.2 application screen.

Click on “Build” icon so that Pwnage Tool can create a custom jailbroken iOS 4.3 ipsw file, which will be used to jailbreak your iPhone 4.

iPhone 4.3 custom ipsw firmware

create iPhone 4.3 custom ipsw firmware file

Exit the Pwnage Tool 4.2 application when done.

NOTE: Create a copy of the iOS 4.3 custom firmware file and place it in the same folder where you have placed all the other downloaded files. Rename this file to .zip and extract it in the same folder.

Step 5: Next step involves restoring your iPhone with the custom jailbroken iOS 4.3 Firmware created in the previous step. Connect your iPhone to the computer and run iTunes. When iTunes detects your iPhone, if you are asked to update your iPhone to the new firmware, DO NOT upgrade it.

Instead, press the Left Alt key and click “Restore” button in iTunes. This will bring a popup window, asking you to select the firmware file. Now, select the custom iOS 4.3 ipsw file you created above.

iTunes will now start restoring your iPhone with the custom firmware file provided by you. This process may take a while, so be patient. After the restore is complete, your iPhone will have jailbroken iOS 4.3.


Step 6: Since, iPhone iOS 4.3 Un-Tethered Jailbreak is yet to come, you will have to put your iPhone in a tethered state. If you don’t perform this step, you will lose the jailbreak.

To put your iPhone in tethered jailbreak, navigate inside the extracted custom 4.3 firmware and move to following location: Firmware >> dfu. Copy these two files: iBSS.n90ap.RELEASE.dfu and kernelcache.release.n90 from this folder and place them inside a new folder on desktop (“TetheredBootUtility”). Also, place the TetheredBoot Utility inside this folder.

Step 7: Power off your iPhone and launch the terminal on your MAC OS and type the following commands:

“sudo –s”. Enter administrator password when asked for. Then, enter the following command:




Replace the <username>with the actual name of the directory. I assume that you have created directories as mentioned in the tutorial.

Press Enter when done! You should notice some activity in the Terminal Windows and at certain point in time, you will be asked to put your iPhone in DFU mode. Follow the tutorial here: How to put iPhone in DFU mode?

If you notice “Exiting libpoison” on the Terminal Window, your iPhone should reboot. Your iPhone is now in a Tethered Jailbroken state.

Troubleshooting iPhone – Jailbreaking Problems

During the jailbreaking process, it is possible that you may encounter certain problems, which you are not familiar with and may require an expert's help. If you require immediate help, you can always refer to the tutorial below for common iPhone jailbreak problems. In this tutorial, you will find answers to most of the iPhone problems. If you think you can add more to the tutorial by providing new iPhone related problems, I shall be more than happy to help you and add your query to the article.

Common iPhone Jailbreaking Problems


PreciousJohnDoe, "How to put iPhone in DFU mode" John Doe Dec 12, 2010

Images Credit:

Pwnage Tool 4.2 images provided by Pwnage

MAC OS X images provided by Apple