Download RedSn0w 0.9.14b1 And How To Downgrade IPhone 3G / 3GS Modem From 06.15.00 To 05.13.04 [Instructions]

Rejoice, owners of iPhone 3G and iPhone 3GS with 06.15.00 modem! The Dev Team has just released a new version of the RedSn0w 0.9.14b1 utility that supports downgrading the modem (baseband). Now all owners of these phone models can easily downgrade to modem version 05.13.04 for subsequent unlocking (unlock) using the Ultrasn0w utility.

This method will allow you to get a device with a fully functioning GPS, which stopped working if you installed a 06.15.00 modem from the iPad.

To carry out the downgrade procedure, you need to do the following:

1. Run Redsn0w 0.9.14b1 (download here).
2. In the "Extras" menu, select "Select IPSW" and specify the version of the installed firmware on the iPhone 3G or 3GS (download here).
3. Turn off your iPhone completely.
4. From the main menu of Redsn0w, select Jailbreak.
5. Check Downgrade from iPad baseband and uncheck Install Cydia if it's already installed on your device.
6. Click Next and follow the instructions to put your device in DFU mode. Be patient, the process can take up to 10 minutes.

At the end of the procedure, you will receive a device with a 05.13.04 modem. Now you can unlock according to our instructions.