Changed Battery and Screen now it wont turn on unless plugged in.

I replaced both the screen and battery in my surface pro 3 i7 256gb tablet. Yes both bridge connectors (Shims) are in place. I even tried swapping the bridge connector from the keyboard ribbon connect to the battery connect in Hope's it was just a bad bridge connector. I've tried factory resetting, uninstalling battery hard drives, hard reboots, visually inspected diodes and conduits running along mother board. Nothing seems to be fried or out. I have swapped different batteries .

I am able to turn the computer on only with the charger being plugged in (OEM CHARGER). It states it is “plugged in, not charging". But as soon as I unplug the power supply it immediately powers off. Does not hibernate or go into sleep mood. Completely dies.

Is something possibly fried?

Are both batterys I'm using really defective? ( 1 battery states it's at 85% or 100% depending how you lay the bridge connector on. Other battery states 0%)

Do I have a defective LCD/DIGITIZER?

Is charging port messed up?

TO ADD THE FIRST INITIAL REPLACEMENT THE UNIT DID RUN WITHOUT BEING CONNECTED TO THE CHARGER. I HOWEVER NOTICED THE UNIT WAS DRAINING BATTERY FAIRLY QUICKLY. IT WAS ON APPROXIMATELY 15 MINUTES BEFORE IT DIED. THE BATTERY INDICATOR READ 63% BEFORE SHUTTING DOWN.