Replaced 4 Parts, still shuts down when power cable removed

Hi all,

I have a Mid 2014 13" Retina MacBook Pro that acquired liquid damage. I had an apple authorized repair center diagnose it and they quoted 3 parts that needed to be replaced: The logic board, the IO board, and the top case with battery.

I replaced the logic board with a used one off eBay that was guaranteed to be 100% functional, and I still had issues with the fans running loud constantly and CPU maxed out. After research, it appeared there were parts in the top case that could cause this, so I replaced the top case with battery, again off eBay guaranteed working, as well as the IO board. I also replaced the magsafe connector as well to be safe.

After a successful rebuild using these new parts, it now operates as expected! No CPU maxed out, no fans running, and when I run an AHT, I get no errors! It thinks everything is fine.

When I boot up the mac, it shows 63% battery and yet it says it isn't charging. When I remove the power cable, it immediatly powers off.

I had reset SMC and PRAM immediatly after the repair. I tried resetting them a few more times, and nothing helps. However, when the power cable is plugged in, it's orange like it's charging. System Info gives me all the info on the battery, tells me the cycle count and temperature and all that, and all health is Normal/Healthy.... yet it doesn't charge.

I can't think of what else to possibly replace... the mac sees the battery, thinks it's connected and fine, yet won't use it. Has anyone ever seen this before?

P.S. I've tried multiple power cables, and cleaned the connectors on the magsafe, even replaced the magsafe connector in the computer... still no luck. If it wasn't for the fact that it powers off when I remove the power cable, you would never expect anything was wrong.