MacBook :: Computer Will Only Charge Battery When On And Open

I took this 13" macbook off of my sisters hands as she has already bought a new one for college. My hope was to save it, as it had stopped working a few months after she spilled some sort of drink on the keyboard. Here's the short story: Took it to local tech support office once it stopped working. They said logic board needed to be replaced, so it's a done deal. Opened it up, cleaned the entire inside of the computer with 95% alcohol and a toothbrush. Let it sit for a day to dry. Turned it on. It worked! But it was finicky in terms of when it would charge and when it wouldn't. Eventually stopped working again when the battery ran out of power and it would not recharge the battery or start up without the battery and just the power. Took it to a friend's house who has the same laptop. Swapped his charged battery into mine. Computer booted up and ran fine. Forgot to test if it was charging consistently by plugging my AC adapter into my computer.

However I did test my AC adapter on his mac with his battery, and that did work fine. So I had eliminated those as the problems and figured it must be something inside the computer. After researching, figured the problem must have been the DC-in board. And I ordered one of these: [URL] and installed it no problem. Now the computer will only charge when it is on and open. If I close the screen it will not charge. And once I open the screen, it shows that it is charging, but 0 battery life, then corrects to the proper amount, then 10 seconds later the light on the mag-power connector comes back on. Another important detail, the computer will not turn on or run while the battery is removed. Perhaps only the part of the logic board that controls the power directly from the mag-connector is fried, but the part the directs it to the battery is ok?

Also just noticed: When the power chord is unplugged, there is a consistent and accurate display of remaining battery life. However sometimes when I plug the power chord back in, it will read 0%, then random other percentages, while the light flashes between green and orange on the top of the power chord. I would like to be able to charge the thing while its closed. Also does this sound like a quark I could just live with? Or does it indicate it will probably fail very soon? Because I could live with this for another few months while I'm waiting to be able to afford another laptop. Even if it meant finding some alternative way to only run it off of only battery power, buying two batteries, and charging them outside of the computer through some third party laptop battery charger.