I"ve got a 5 recently upgraded to ios9. Also changed the battery recently. After 9 upgrade, phone started rebooting all the time. Only worked if plugged in and battery had near 100% charge. It would reboot, but typically successfully. This then got worse and now it just reboots to some system level text about 5-6 lines with the first line the subject line here. I tried initially fixing with reiboot and recovery mode both with and without iTunes. Then it wouldn't boot at all, and I put it in DFU mode and tried to do a restore with iTunes and that fails. Error message was like a 4005 or something like that and the "learn more" just says stuff like try again on a different mac, upgrade iTunes, blah blah. Is this a hardware failure? Anything else anyone can recommend?