Released June 2012, Model A1278. Intel processor with Turbo Boost, Up to 512 MB DDR5 Video RAM

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

Ok so, my macbook pro 9,2 has three major problems in the aftermath of the spill.


1. 4 keys do not work, I suspect an electrical short damaged them beyond repair. A bluetooth keyboard restores function of these keys. I might replace the oem keyboard with new keyboard. This is the least of my worries and could easily be fixed but may provide context to problem.

2. The Battery and supply of power to the laptop are malfunctioning. The laptop does not turn on with a simple press of the power button. This causes the light on the side of the case facing the users lap to light up, the fan runs for a few seconds, then it all shuts down. I can successfully turn on the laptop by holding it until the chime.

When on and plugged in, the magsafe charger will always show a green light regardless of battery's charge level. While plugged in, the battery percentage displays correctly and it acknowledges that it is plugged in. However, it states that the battery is not charging. It also states that the laptop is on adapter power. However, the battery drains steadily during use.

Furthermore, When off, the magsafe charger will display a green light and not charge the battery. An SMC reset (or soft SMC reset? I'm not sure what to call it because I hold down shift, option, and control and just tap the power button once. I do not hold it down to turn the computer on because the battery won't charge while on) will cause the magsafe light to change from green to orange and charging will begin. However, charging is very slow. 12 hours charging results in 15% battery.

3. CPU is being hogged by kernel_task. About 250-350%. Always. I understand this is probably reactionary by the computer to one of the problems I have.

Notes: Before any work began on cleaning, i received the error 400000: IPBR 9.165. I found a thread saying that this alluded to corrosion on the connectors and surrounding board connections where the battery connects to the logic board. Cleaning these areas and surrounding areas (as well as dc-in board) with 91% isoproply alcohol has removed this error.

The cleaning process did not damage any internals of the computer or cause any of these problems. The problems arose before cleaning occurred and persisted in the same manner afterwards.

Tasks already completed

-I spilled coffee

-I turned it off, removed battery, let dry

-Ran diagnostics, receieved error IPBR 9.165

-Ran SMC and PRAM resets

-Thoroughly cleaned logic board and dc-in board

-Re-ran diagnostics, no more error code.

Soooooo, I'm planning on replacing the dc-in board. Then the battery. But I'm kind of convinced it's neither. The fact that it charges, but only after an smc reset, suggests the battery is functioning. As does a reading of "good" for the battery from the OS and from Coconut Battery. The fact that it charges, suggests that my Magsafe charger is fine, although I'm borrowing another to see if there is any effect on charging speed.

Why it doesn't charge the battery while is confusing. I've found another user with a similar problem who says that watching the battery % reading, it actually would go up from time to time while running. So maybe the charging speed, or power supply from the magsafe, is so low that the battery doesn't charge fast, doesn't register as being charged while laptop is on, and doesn't supply enough power to the laptop to rely on it for all it's power while operating (causing it to deplete power from the battery).

If a new adapter is a fix, it still won't solve my kernel_task issue. I've read others having relief from this issue after replacing the battery. But I'm really stuck there.

I'm kind of lost, am I missing something? Please don't say it's the logic board.


So I Charged the battery completely. As painful as it was, it seems to have fixed the Kernel_task overloading and the battery is draining a much more normal speed. However, the battery does not charge while the laptop is on. I still have yet to try soMeone else‘s Magsafe charger. I think that Mine is definitely failing. I will post again if the probleM re-arises.

Answer this question I have this problem too

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2 Answers

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.

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.

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Thanks for your response, I will post battery readings the next time I have it on, and pictures of the board where the spill dried and where I found corrosion when I take it apart on Thursday.

Your logic also makes great sense with the dc-in board. I won't waste my time replacing it. The battery also seems to be functioning fine. It was a re-calibration of the battery that relented the kernel_task response.

I'm convinced it is a logic board issue. But a livable one now that the kernel is draining battery like its going out of style. Till next time, Thanks.


So after another look, there is more corrosion and possibly damaged transistors. The first image shows the area the spill affected. The second image is the 3 corroded parts of the board. Thank you to those that take a look.


That's audio circuit, who cares about audio right now? Check R7021 & R7022.


im having trouble finding a schematic to identify those two.


Cmon man, 20 seconds of google...

You're getting paragraphs of howto here, put in the slightest bit of effort on your side!


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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.

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Bulging caps and resistors, have you ever even opened one of these things, or just copying and pasting same answer to every question ? :(

R7051, R7052 ,R7021, R7022, and traces between these and U7000.

And NONE of it will be bulging.


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Sean McGoldrick will be eternally grateful.
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