Happen twice to me within 2 month due to battery failure. Battery need to be replace with new one.
First case, flashed stock firmware 4.4.2 from sony, battery died in 2 days after and new battery replaced.
Flashed custom rom carbon..everything run smooth. Last week i'm flashed back stock firmware 4.4.2 and battery died again.
Just get new battery replacement today and manage reassembled my own.
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