Hi and Welcome. My Name is ***** ***** I look forward to assisting you today with your question.
First we can reset your iPhone and see if it works or not. Press and hold down the Power button and Home button at the same time until it shows the Apple logo. When you see the Apple logo, release the buttons and let it boot.
Please let me know if that didn't work, so we can continue troubleshooting.
It is possible that the battery has failed. Connect the iPhone to your computer for 20 minutes. Then press and hold down the Power and Home button for 20 seconds and this will boot into recovery mode. Let me know if it still not turning on
How old is this iPhone ? When you connect it to your computer, does your computer make any sound ?
How old is this iPhone ?
Disconnect it from your computer and reconnect it. Does your computer make any sound ?
I'm sorry, this is an hardware issue. Either the internal board or the battery has failed. The only way to know is by taking it apart. I'm sorry, but you have to take in to the Apple Store to get it replaced. Since it is out of warranty, it would cost $299 to get the phone replaced. See here --> https://www.apple.com/support/iphone/repair/other/
We've already tried resetting it and there is no other option left since your computer is not recognizing. You need to take it to the Apple Store. You can make appointment on Apple store from here --> http://www.apple.com/retail/geniusbar/
If you have any questions or would like any additional information, please don't hesitate to ask
FYI If it is the battery, the cost to replace is $79
If you are not satisfied with the information I provided and if you don't want to pay, then you don't have to pay. It is your choice.
If you would like refund, please contact/email to *****@******.*** for refund.
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