Well, this is quite a tough one if you’re pretty new in this jailbreaking and unlocking world!
Iphone 2G is quite a pretty tough one with the release of OS 3.1.3. Warnings has been made. iPhone 3.1.3 firmware updates the baseband to 05.12.01. If you update your iPhone to new firmware, it will lock your phone permanently and it will become a useless phone. iPhone dev team has released redsn0w 0.9.4 for iPhone 2G and iPhone 3G users to jailbreak the iPhone 3.1.3 firmware.
Well if you’re using redsn0w and trying to jailbreak please ensure you are connected either with wi-fi or internet data plan. Otherwise the process will not complete since it requires an active internet connection. This is what happened to my friend. His spent the whole night trying to jailbreak and unlock but ended up with ibrick when his credit ran out.
iPhone 2G users can jailbreak as well as unlock the phone with redsn0w 0.9.4, but iPhone 3G users can’t unlock it with this jailbreaking tool. So, iPhone 3G unlockers should stay away from iPhone 3.1.3 update and they should not use redsn0w 0.9.4.
The redsn0w 0.9.4 tool doesn’t work with iPhone 3GS, newer versions of iPod Touch 2G and 3G. I would recommend you to wait for an announcement from iPhone dev team.
If you have done similar things do not connect to iTune or it will force restore 3.1.3 into your iphone 2G and lock your iphone. Only emergency call is allowed. Mind that!
But don’t worry sn0wbreeze and redsn0w are here to help.
Using sn0wbreeze it is not clear even after using iREB to prevent 1600 iTune error since they insists on us going to DFU mode which is the black screen when actually you are required to into Crash DFU mode the white screen to bypass iTune error due to custom ipsw being installed. sn0wbreeze gave a video tutorial to go into DFU mode as well.
The best unlock and jailbreak tool for iphone 2G. After you point it to your current ipsw 3.1.2 it will automatically download the latest ipsw and patched the kernel with additional Bootneuter to unlock the carrier lock.
There is the tutorial on how to go pass DFU mode by pressing home button with additional 16 seconds which is different than normal DFU mode that is 10 seconds only. Total is 26 seconds and your DFU mode will break into Crach DFU white screen and the jailbreak will be done.
All you need is iClarified, oldapps and redsn0w 0.9.4.
The downloads file required are shown below.