My phone is unresponsive, what should I do?

[AC Question]

My phone is unresponsive

I have a Samsung Galaxy S4. I factory reset the phone through the setting and then updated it to lollipop. My brother was playing on it that night and it shut off on him. He is not sure if he ran the battery all the way out or if it just shut off. He thought at the time that the battery died but know he is not sure. He plugged it in to the charger. A couple hours later I went to turn it on and nothing happened. No vibrations, lights, sound, LED's, or screen at all. I tried different chargers and a good battery. It is not recognized by my computer. I took it to best buy and Verizon and they had no idea. Has any body else had this problem? Is there any thing i can do?




addition
I cant access the download mode

 

[Ian Morgan2]

Re: My phone is unresponsive

Go to How-To Geek....see the article :-What to Do When Your Android Phone or Tablet Won’t Turn On
Extract as follows :-
Pull the Battery or Long-Press the Power Button
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How to Power Cycle Your Gadgets To Fix Freezes and Other Problems
Have you ever had a smartphone, laptop, tablet, or any other electronic gadget become unresponsive? The surefire way to recover... [Read Article]
Like other operating systems, Android can sometimes hard-freeze and refuse to respond. If Android is completely frozen, your device may be powered on and running — but the screen won’t turn on because the operating system is frozen and not responding to button presses.

You’ll need to perform a “hard reset,” also known as a “power cycle,” to fix these types of freezes. This cuts the power to your phone or tablet entirely, forcing it to shut down and boot back up.

On a phone or tablet with a removable battery, you can remove the battery, wait about ten seconds, and then plug the battery back in and boot it up.

On a phone or tablet without a removable battery — that includes most modern Android devices — you’ll need to long-press the Power button. Press your device’s Power button and hold it down. You should only have to hold the Power button down for ten seconds, but you may have to hold it down for thirty seconds or longer. This will cut the power to your phone or tablet and force it to boot back up, fixing any hard freezes.