Galaxy s3 battery problem.. plzz read it and help me sove

[prajjwal]

My galaxy s3 is a bit old that is about 2 years.. when i remove my battery it takes it up and sometime down For eg sometime 58% then i remove it goes to 10%.. i have also changed my battery.
My Nearer phone repair shop(not samsung centre) he said that my phone has some short of shorting..
should i may get my motherboard change or anything...

 

[KaosMaster]

I would charge the phone to 100% with the phone off and odin flash with special options enabled. I can assist you with this but you need to back up all your data. Message me on hangouts if you would like to proceed