Why does my Galaxy S3 keep shutting down?

[AC Question]

Galaxy S3 keeps shutting down

My Samsung Galaxy S3 recently started shutting down for no apparent reason, and only removing the battery and replacing it would make it work again. The lock screen freezes when I swipe it, and then... blackness. The problem had been getting gradually worse, but when I sent it back to Tesco repair shop (I bought it from them) they said the engineers haven't been able to replicate the problem! It doesn't appear to have anything to do with charging/the charger, and just happens randomly. Ideas please? (It was bought in December 2014)

 

[dpham00]

Re: Galaxy S3 keeps shutting down

See if the battery is snug in the compartment. I had a problem with occasional restarts that was because the battery wasn't snug. I used some paper as padding to make sure that the battery was snug in its compartment