Why does my iPhone keep restarting?

It sounds like your battery has gone bad.

"You need to do a DFU Restore,

1. Connect the device to your computer

2. Shut down the device

3. Press the Power and the Home buttons at the same time

4. After 10 seconds release the Power button but continue holding the Home button

until you see a popup from iTunes saying ""iTunes has detected an iPhone in recovery mode""

5. If you have been successful your device screen will be completely black/blank (this is 'DFU Mode')

6. You can now proceed and restore to the latest firmware using iTunes

This should fix your problem"

I have a son who decided to jump in the pool with his iphone 4 in his pocked. He put it in the rice for a few days and the phone turned on, but it would not charge past 4% and it kept shutting down after a few minutes. I managed to do a backup in itunes, because it will resume after the phone restarts and starts up again (you have to have a lot of patients for this) but it would not restore anything because it kept restarting. Well I ordered a new battery from ipod Battery Depot for $22.94 plus shipping of $5.96, I installed the battery then went into itunes and did a restore from backup and everythings works great now. I am a 69 year old lady, and if I can do it anybody can. Good luck.

"Oh boy this could be a number of issues. I would have to start this with some questions.

What model is it?

Does it hold or show a full charge before restarting or on home screen?

Does it restart back to the home screen? Lock screen? Apple or iTunes logo?

When you plug it in does it show the battery charging or blinking?

Does it reboot only when the charger is plug in or before?

Must you leave it plugged in to function?

Based off the comments above, I would say it is one of 3 thing.

-You need a new battery which is not uncommon for iPhone 5 and below.

-You have a little bit of water damage on the logic board.

-You have a Jammed power button.

-I would normally say charger port to, but you said it was recognizing the charger.

Please send me some answers, I am happy to help!"

Something else must have happened to it. What you should do is plug it into your computer, hold down the power and home button and as soon as the screen goes black just hold down the home button for up to 30 seconds, your itunes should finally give you a message and enter restore mode where you can update through itunes and fix any software issues that might be causing this glitch...

I was having a very similar problem with my ipod classic a few months back. I had no idea what the problem was and nothing really seemed to be making sense. After some extensive testing and switching out of parts, I found out that it was the hard drive cable that was causing my ipod to continuously restart itself. I think the problem occurred because I left my ipod in my car for a few days and it got excessively hot in there. I imagine your problem is something similar to this.