It would help if you could also post the model number when asking for help, to give us an idea of what you have. I cannot link a manual to you without it.
3 blinks of the power charging light means a its a power issue and could be several reasons for it.
You could try a power reset. unplug the charger and if the battery is removable, remove it. if its not removable, leave it in. Hold the power button down for 30 seconds and release. Do this several times. Then plug the cord in as see if it works.
You can try disconnecting the battery, even if its built in, disconnect it. Then see what happens.
If none of the above work, its most likely something that failed on the motherboard.
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