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I got a new battery for lg 8.3 vk810 accidentally I let it completely die now I can’t get it to charge or turn on I tried the 20second thing but it still won’t do. anything. Also my screen is very dim?

Got the new flex cable in and its working great thank you for your help

Try disconnecting the battery for a few minutes then replace battery and before turning it on plug it in and let it charge . Leave it plugged in for a day. see if this helps just in case you need a guide LG G Pad 8.3 Battery Replacement