Hey all, having a bit of a problem with my 3GS, bought the second hand the other day off a friend. He told me it wouldnt update in iTunes,ok, so I thought I could fix it.

Connect to iTunes and 3/4 through it throws up 'update cannot complete (Error 29). Now all it does is boot onto the Apple Logo, and the screen then goes blank, i.e no backlight but black lines/pixels are shown almost like a loading screen, and on comes the Apple Logo again. The cycle takes about 1 minute to circle.

This only happens when it is plugged in via usb, so I assume the battery is borked. Other users are complaining that you need a OEM battery and this gets rid of Error 29 in iTunes, others say its because of water damage, and more say it can be fixed by running iRecovery. See here: Restore Boot Cycle Error 29 Fix | MediaCrave

My problem is I cant seem to get it in or out of recovery mode/dfu because it doesnt boot for long enogh to be recognized by Windows/iTunes, so people, what would be my best plan if action to get this lovely 3GS back up and running? Im thinking replace the battery and see what happens for there...

Thanks for reading. Looking forward to replies.