Keeps Shutting OFF (battery shows fully charged)

I think you need to replace the battery pack, this is a symptom of a failed battery pack.

My phone keeps turning off by itself. ' Android Forums

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Sep 22, 2015 - Um my phone keeps turning off by itself. And its really really starting to get annoying. IDK if it was some app or an update. Anyone else having ... Phone unexpectedly shutting off without notice
Feb 2, 2016
help.my phone keeps turning on and off by itself
Dec 23, 2015
Randomly Turning Off?
Oct 26, 2015
Phone keeps shutting off by itself
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My Phone Keeps turning off and then turning itself back on ...

https://www.ifixit.com/.../My+Phone+Keeps+turning+off+and+then...

iFixitwhen i turn on my phone and it does its power up, i wait for my service to come on. before the service gets turned on the phone restarts itself everytime. it ...

There are two thing you can try:

1. Shut it down, remove the battery and replace it again.

2. Back up all your data and restore it to factory settings.

It is possible an app is make it hang, that's why the factory reset might work.

Cell phone batteries have what is called a "memory" over time if they are charged without being fully drained they can start to not hold a charge. Unfortunetly the only fix for an issue like yours is to purchase a new battery. Your local retailer / service provider should have batteries in stock or they can order one for you.
It is recommended to allow the batteries to drain completely before charging, then allow at least 8 hours or more to fully charge. Most cell phone will show a full charge after a few hours, but this is more a fault with the software that check the batteries charge, then an actual indication of the battery being fully charged.

If you can reach inside the computer and rub the battery contacts gently to remove the corrosion ,which is invisible , this will help greatly. Sometimes even a new battery will suffer the same. Clean the battery contacts also turn off the laptop and charge it fully do this on a regular basis. Say once every 2 months

my c510 no ntew. coverageand battery cannot charge. you must use a sony Ericsson battery.

when you purchased the battery minimum charging is 48 hours.please charge fully battery and then use it.I hope your problem will be solved.sometimes we are not charged the full battery and then battery life is also effects.

sounds like a fryed battery

Digital cameras require lots of power. Bad electrical contacts can cause lots of problems so battery and camera contacts must be cleaned properly. Batteries may be fully charged, but will be viewed as low if contacts are not really good. The LCD screen is a low steady load, but when lens extension, optical zoom, focus, and flash charging are added in the capture mode; the load is very heavy. Bad contacts make cameras do strange things like making bad pictures or shutting off with the lens out.
Do not overcharge.
Reset by removing power up to one month is the ultimate non-physical repair for DVD recorders and other software using digital devices. Digital cameras reset to original settings if batteries are removed. Time required varies with function and camera, but try one minute. Check display and setup menu for non-auto functions and date/time. Remove extra memory to eliminate this as a possible problem. Insert fully charged batteries and restart the camera.

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