I've got an iPhone 3GS I would like to sell. So I erased all content through the Settings menu. The iPhone won't start up anymore. It was stuck on the Apple logo. A friend of my who is "good with electronics" was on a holiday, so the iPhone was in my bag for over a week. Now he is back, the iPhone 3GS was dead. The battery has drained (not so weird after a week ). Unfortunately the iPhone will not go into DFU mode anymore It's stuck in a loop. First you see the famous Apple logo. After a couple of minutes the screen will go off, then showing the red empty battery icon. And after a short while the Apple logo is back on. It keeps repeating this logo/battery loop. It is not possible to go into DFU mode. I tried different USB cables, a power adapter, the USB port on my MacBook Pro. It does not matter. The iPhone 3GS is jailbroken (iOS 4.1) with Pwnage. What can I do/try?