My iPhone 3G will only power on when plugged into mains. It only powers to the silver Apple logo, and then goes to a faint image with a line through it after round about 45 seconds. Can you help me? Thank you.
I'd do the following:
1. charge it for at least 5 hours continuously without unplugging it.
2. Unplug the charger and hold the power button for 8-15 seconds.
I think that your phone's software is corrupted and is in recovery mode.You can solve this by -
1) Holding power and home button for 20m seconds.
2) Hold only home button(i.e. leaving power button) for 5 seconds.
3) Wait for 20 seconds and see whether your iPhone comes back to life or not.
have you tried restoring it via itunes? It will delete everything unless you have a backup. maybe your lcd screen is going bad. or if it will only power on with the charger in, you may need a new battery