Coffee Spilled, Charges when off (Extremely Slowly), Doesn't when on

Replacing the DC in board makes no sense. This just sends power to the machine - it has no say in WHEN power gets sent to the machine. If it sends power while it is off, it works. None of that wishful thinking crap so common to internet forums, that the easy $5 fix is the fix!

Most likely a high side current sensing issue on the charging circuit. U7000 limits the charger's power if it thinks it is using too much power. The only way to tell how much AMPERAGE a circuit is using is to be in the "middle" of it to measure. U7000 is not in the middle, so it can only measure voltage. What it does here is it attaches itself to the top and bottom side of a very low impedance resistor(R7020) on the line from the charger to the buck converter for the main 12.6v rail. It measures the voltage on each side of this resistor, and calculates the amount of amperage the system is using based on the voltage drop across the resistor. R7021 & R7022 report the voltage at the top of R7020, and the bottom of R7020, to U7000, which U7000 then utilizes to calculate how much current the system is using. Smart thinking!

Traces between these resistors and then to U7000 are blown, or the resistors themselves have gone bad. Usually one of the 10 ohm.

If anything in this circuit is off, it will not report the proper power usage to the ISL6259, and it will not allow full power to go to the machine.

Which means it may charge during a low power state, such as being off - but not during a high power state, such as being on.

You need to post pictures of where the board is corroded, has red probe points, or is F'd up. You have no measurements, no pictures, so I am just guessing. My guesses are about the best you'll find anywhere, and are nearly always right, but even I need information to work with!!

The quality on this video is junk, but explains your problem and possible solution. https://www.youtube.com/watch?v=i_ziYgCR...

As usual, you will have to be comfortable with a soldering iron, multimeter, schematic, and above all brain usage if you are to solve this. If this works I can help guide you to a working machine, if not give up before you waste $100+ on a new charger or DC in board.

Considering the fact that your Mac turns on, I don't think that the logic board is fried. iFixit provides tools, guides and parts describing how to fix your MacBook. Here's the problem: the keyboard is partially fried. This requires that you gut the entire MacBook. Apple has hit their repairability score by making the palmrest, trackpad, keyboard and power button all one piece, so fixing the keyboard will be a lot more expensive than you may have thought it to be. The battery may have also suffered eternal damage. Because you have a sealed lithium-ion battery, any temporary short can cause problems with the battery. Use a Phillips #00 screwdriver to remove the bottom cover. Use a spudger (search the iFixit store if you don't have one. Make sure to use the static-safe spudger) to remove the battery connector (this connector is very fragile, so be careful!), then use an iOpener (it looks like a long bag from iFixit) to loosen the adhesive that holds the battery into place. Carefully look at the battery. Is there any liquid damage or are any of the battery cells bulging? If so, this is bad. Don't put the battery back in. Instead, order a new battery (again, iFixit has batteries galore). DO NOT THROW THE OLD BATTERY IN THE TRASH!!! This is environmentally irresponsible, not to mention incredibly dangerous. Take the battery to an electronics recycling center. Check with your local electronics stores to see if they take lithium-ion batteries. Next, take out the logic board and remove as many components from the device as possible. There are many different types of screws. You're going to need several unique bits, including the Apple Pentalobe and the triwing bit (iFixit has all of these). Use the Magnetic Project Mat (available from iFixit) to keep track of the copious number of screws. Take lots of pictures, so that you know how to put your Mac back together. Examine the front and back of the logic board. Bulging capacitors and resistors are bad, and you want to avoid touching them. If there are bulging capacitors or resistors, then you may as well declare your Mac dead. If the logic board seems okay, then continue with the palm rest. You will need to replace this. Order a new one from iFixit and use their replacement guide. I hope this helps.