iPhone dev team has released an updated Pwnage tool 3.1.5 for Mac, which is compatible with iPhone firmware 3.1.3 and can be used to create custom 3.1.3 firmware.
You can jailbreak original iPhone, iPhone 2G, iPhone 3G and iPhone 3GS (old bootroms only with baseband 04.26.08), iPod touch (1G, 2G None MC models; Prerequisites for iPod 2G is, it should be pre jailbroken) running on iPhone 3.1.3.
The custom .ipsw firmware created by Pwnage tool can update iPhone to firmware 3.1.3 without updating its baseband so that it can be unlocked to run any carrier SIM.
If you have previously relied on blacksn0w unlock for your jailbroken iPhone 3GS then this is not for you, iPod Touch 3G is also not supported.
Follow this step by step guide to jailbreak your iPhone running on iPhone firmware 3.1.3 with Pwnage tool 3.1.5.
Download and Install latest iTunes software.
Start iTunes and sync it with your PC so that it backs up all your important data.
Download Pwnage Tool 3.1.5 and original iPhone OS 3.1.3 for your version of iPhone.
Start Pwnage tool and select your device.
Pwnage tool 3.1.5 will automatically detect correct firmware for your device.
Click “No” when Pwnage tool asks you “Do you have an iPhone contract that would activate normally through iTunes?”.
Clicking “Yes” will update your baseband to the latest version making your device almost impossible to unlock. Click Yes only if you are on officially supported carrier like AT&T.
Pwnage tool will now create custom .ipsw file for your iPhone which will be jailbroken.
You will see “ihaz success” screen when Pwnage tool is done with creating a custom jailbroken firmware for your device.
Once your custom .ipsw file has been created successfully, its time to restore your iPhone to this custom cooked iPhone 3.1.3 firmware. Click on your Phone icon from sidebar in iTunes.
Now press and hold “Left Alt” button (Shift button on Windows) on keyboard and then click on “Restore” button (not “Update” or “Check for Update”) on iTunes and then release the “Shift” button.
This will make iTunes prompt you to select the location for your custom created firmware 3.1.3, select the custom .ipsw file and click on Open.
Relax while iTunes does the job for you. It will go through few automated steps and install the new iPhone 3.1.3 firmware on your phone. Your iPhone screen at this stage will be showing a progress bar indicating the progress of the installation. After the installation is done, iPhone will be restarted automatically and now you would have a jailbroken iPhone/iPod touch on firmware 3.1.3.
Unlock iPhone on iPhone firmware 3.1.3
You can use ultrasn0w unlock for iPhone 3.1.3 to unlock your iPhone to work with any carrier SIM (baseband 04.26.08 only).
-Once you are done with jailbreaking and unlocking your iPhone, you can restore all your important data to the newly installed firmware 3.1.3 by restoring the back up you made in Step 2 in iTunes.
This guide is for testing and educational purposes only. We won’t be responsible for any loss of important data or malfunctioning of your device. You have been warned!