2012 MacBook Pro No Longer Powering On

[m1maverick]

A few years ago I purchased a liquid damaged 2012 MBP. The system was sold non-functional, as-is. Given the low price I decided to purchase it and, upon receipt, plugged it in and lo and behold it fired right up. I added memory, a SATA SSD, and a brand new battery. I was pleased with the total cost to buy and add the missing components (essentially the battery as I had everythine else).

I used it for a few weeks and then suddenly it stopped working. It was essentially dead...it wouldn't work with the power adapter or battery. In fact the power supply light no longer illuminated (orange or green). OK, it was a risk and accepted that its working was a fluke. At one point I tried powering it on again and...it worked!

Fast forward to today where I was working with it and it suddenly powered off and I cannot power it back on. It is exhibiting the exact same symptoms from a few years ago. I pulled the back cover, checked the connections which were easily accessible. I assume the problem from years ago has returned. Why? I have no idea.

So I post asking if anyone knows where I might look. The current symptoms are no power...nothing...from the power adapter or battery. Same lack of light from the power adapter. It's puzzling to me how it can work, stop working, resume working for a while, and then suddenly fail again with the same symptoms.

Any suggestions on what to look for?

 

[MBAir2010]

what size?
the 15" and 17" have faulty GPU and cable problems that can be repaired.
there are many threads here about pinpointing the exact problem here.

 

[B S Magnet]

what size?
the 15" and 17" have faulty GPU and cable problems that can be repaired.
there are many threads here about pinpointing the exact problem here.

No, it won’t be a faulty GPU.

That issue is confined to the AMD-equipped GPUs on the discrete graphics setups in the 15- and-17-inch 2011 models, along with some 2010s. The 15-inch 2012 unibody model was bundled with an nVIDIA GeForce GPU.

A few years ago I purchased a liquid damaged 2012 MBP. The system was sold non-functional, as-is. Given the low price I decided to purchase it and, upon receipt, plugged it in and lo and behold it fired right up. I added memory, a SATA SSD, and a brand new battery. I was pleased with the total cost to buy and add the missing components (essentially the battery as I had everythine else).

I used it for a few weeks and then suddenly it stopped working. It was essentially dead...it wouldn't work with the power adapter or battery. In fact the power supply light no longer illuminated (orange or green). OK, it was a risk and accepted that its working was a fluke. At one point I tried powering it on again and...it worked!

Fast forward to today where I was working with it and it suddenly powered off and I cannot power it back on. It is exhibiting the exact same symptoms from a few years ago. I pulled the back cover, checked the connections which were easily accessible. I assume the problem from years ago has returned. Why? I have no idea.

So I post asking if anyone knows where I might look. The current symptoms are no power...nothing...from the power adapter or battery. Same lack of light from the power adapter. It's puzzling to me how it can work, stop working, resume working for a while, and then suddenly fail again with the same symptoms.

Any suggestions on what to look for?

I dealt with a liquid-damaged 2009 MBP several years ago after I incidentally exposed it to, of all things, coconut water (please don’t ask).

Though this may not be entirely analogous, I was able to get it to partially run after immediately cleaning and drying it in a tub of rice, but the more important takeaway here is it wouldn’t last for long. Liquid damage, especially if it is left to sit in any way for any length of time, will trigger corrosion on the board. Eventually, that corrosion will continue and begin to take out the solder points. What probably happened with it intermittently working previous is a solder point was right on the edge of giving out, and in the time since, probably corroded through, giving you a dead (for now) system.

For your next step, you might need to disassemble your MBP and take out the logic board to visually inspect it for this corrosion (no, that wasn’t a pun, to those of you reading who are old enough to get it). This will, at the very least, given you an indication of how much damage the prior owner’s spill caused. That will also give you a sense of how much work will be needed if you want to have a fully running system.

 

[m1maverick]

what size?
the 15" and 17" have faulty GPU and cable problems that can be repaired.
there are many threads here about pinpointing the exact problem here.

It's the 13" model.

 

[m1maverick]

I dealt with a liquid-damaged 2009 MBP several years ago after I incidentally exposed it to, of all things, coconut water (please don’t ask).

Though this may not be entirely analogous, I was able to get it to partially run after immediately cleaning and drying it in a tub of rice, but the more important takeaway here is it wouldn’t last for long. Liquid damage, especially if it is left to sit in any way for any length of time, will trigger corrosion on the board. Eventually, that corrosion will continue and begin to take out the solder points. What probably happened with it intermittently working previous is a solder point was right on the edge of giving out, and in the time since, probably corroded through, giving you a dead (for now) system.

For your next step, you might need to disassemble your MBP and take out the logic board to visually inspect it for this corrosion (no, that wasn’t a pun, to those of you reading who are old enough to get it). This will, at the very least, given you an indication of how much damage the prior owner’s spill caused. That will also give you a sense of how much work will be needed if you want to have a fully running system.

I have no idea what liquid entered the system (though it didn't look like anything sticky). Upon initial receipt of the system I disassembled it to perform a cleaning. The PCB area around the ports had some obvious signs of liquid exposure. I used some IPA to clean the affected area clean. I reassembled and all worked as expected.

Until yesterday it's been reliable (though it doesn't see regular use) ever since the first issue. It's odd that it was working fine and then it just powered off (I wasn't using it at the time so I am unsure if it just powered off or went to sleep and now won't wake, whatever it is it's no longer powered on).

I am thinking maybe I'll disassemble it and throw the board into my ultrasonic cleaner to ensure I remove all traces of whatever was spilled. Then inspect with my loupe under light.

 

[TheShortTimer]

It's the 13" model.

Even if it was the 15" (or even 17") model the GPU definitely would not be a factor here because as @B S Magnet magnet already pointed out, the 2012 range are not affected by this issue but it continues to be a source of confusion for many. Besides, I highly doubt that GPU failure would prevent the machine from powering up.

I hope that you're able to correct the problem.

 

[m1maverick]

One of the things I forgot to do was check the obvious. So I hooked the power supply up to a 2006 MacBook and it powered on just fine. I then reconnected the power supply to the 2012 and now the light is illuminated green. However the system still does not power on.

I decided to try a second power supply and it is exhibiting the same issue as the previous one was before this test...no lights at all. So I reconnected the previous power supply and I am going to let it sit awhile and see if it magically returns to life later today.

 

[MBAir2010]

another test is to boot via logic board
if you could find the 2 power nodes or pins on your MacBook pro (look this up online)
place a small flat head screw driver on those and wait for the chime.
i think your power button key is defective.

 

[m1maverick]

another test is to boot via logic board
if you could find the 2 power nodes or pins on your MacBook pro (look this up online)
place a small flat head screw driver on those and wait for the chime.
i think your power button key is defective.

Good idea for a test, I never even considered this.

 

[aurora72]

Good idea for a test, I never even considered this.

In the original post you've said that "it would suddenly power off" which means that the power button cannot be involved. I think it 's caused by corrosion in some parts on the logic board. Corrosion might be causing short-circuit and that might be preventing the logic board from powering up. Look up this thread: Mac mini no power to logic board In this thread I talk about my liquid / vapour damaged 2005 Mac mini which wouldn't power up. After I disassembled the logic board of that Mac mini, I noticed that one of the 2 Video RAMs had intensive corrosion between the board and the RAM which could be seen only by looking at the board from its edge i.e. it wasn't noticeable by merely looking at it from above. I noticed that hidden corrosion after my last post to the thread, i.e. I mention it for the first time here.

In short, it would be best if you disassemble the logic board and closely scrutinize it. If you decide to take it to a repairman, see this channel: https://www.youtube.com/c/NorthridgeFix

 

[m1maverick]

In the original post you've said that "it would suddenly power off" which means that the power button cannot be involved. I think it 's caused by corrosion in some parts on the logic board. Corrosion might be causing short-circuit and that might be preventing the logic board from powering up. Look up this thread: Mac mini no power to logic board In this thread I talk about my liquid / vapour damaged 2005 Mac mini which wouldn't power up. After I disassembled the logic board of that Mac mini, I noticed that one of the 2 Video RAMs had intensive corrosion between the board and the RAM which could be seen only by looking at the board from its edge i.e. it wasn't noticeable by merely looking at it from above. I noticed that hidden corrosion after my last post to the thread, i.e. I mention it for the first time here.

In short, it would be best if you disassemble the logic board and closely scrutinize it. If you decide to take it to a repairman, see this channel: https://www.youtube.com/c/NorthridgeFix

That is an assumption on my part. In my third post I mentioned I wasn't sure if it just powered off or if it went to sleep and won't wake. I assume it powered off as when it would sleep I was able to wake it by pressing on the trackpad. It's no longer doing that.

Regardless it's not powering on and I think inspecting the power button is at least worth considering.

 

[MBAir2010]

we just troubleshoot things wrong with our macs
i worked at a repair shop and was the apple fixer upper guy from 2011-14
most problems were liquid spills and we saved many laptops during that time.
there are many remedies and approaches in fixing MacBooks.
what is tough is we cant see the visuals as a repair shop,
and think the easiest and most successful way to repair a MacBook., then advise.

the best fix was removing a cookie crumb lodge in a MacBook air 2012 ssd drive slot.
the owner worked at a bar, and boy did i get free drinks for a while!
there would be no way i can fix that on a forum.

 

[avz]

That is an assumption on my part. In my third post I mentioned I wasn't sure if it just powered off or if it went to sleep and won't wake. I assume it powered off as when it would sleep I was able to wake it by pressing on the trackpad. It's no longer doing that.

Regardless it's not powering on and I think inspecting the power button is at least worth considering.

Have you tried removing(disconnecting) the battery and powering on with just a charger connected?

 

[m1maverick]

Have you tried removing(disconnecting) the battery and powering on with just a charger connected?

I did, as it so happens I had just ordered a RAM upgrade for the system and needed to remove the back cover to install it (the failure happened prior to any work done on it so it wasn't new RAM which caused the fault). I left it unplugged (power and battery) for about 30 minutes and no change.

Only change I've seen since is when I connected the power supply to the MacBook (as described in post seven)

 

[bobesch]

I 'd suggest to go for a DC-In-Board replacement ...

 

[m1maverick]

I 'd suggest to go for a DC-In-Board replacement ...

I am definitely going to look into this. However I have some other things to take care of so I won't be getting around to it for a few weeks.

 

[m1maverick]

Today I decided to pull out the system board and it looks to be in fairly good condition. I am struggling with the decision to purchase a DC-In-Board or just run it through the ultrasonic cleaner (unless someone has a reason why I should not do so).

Disassembly wasn't really that difficult but I'd rather not go through it again so for a few bucks I should just replace the DC-In-Board.

EDIT: Here's a pic of the DC-In-Board removed from the system:

 

[bobesch]

Today I decided to pull out the system board and it looks to be in fairly good condition. I am struggling with the decision to purchase a DC-In-Board or just run it through the ultrasonic cleaner (unless someone has a reason why I should not do so).

Disassembly wasn't really that difficult but I'd rather not go through it again so for a few bucks I should just replace the DC-In-Board.

EDIT: Here's a pic of the DC-In-Board removed from the system:

View attachment 1960333

Good luck - wish You success!

 

[m1maverick]

UPDATE: I've got the DC-In-Board and System Board in the ultrasonic cleaner now. It'll be done in a few minutes and the next step is to dry it off.

Question: Should I reassemble and try it out? Or wait for the new DC-In-Board to arrive (about a week from now)? I don't mind waiting but I'd be curious to see if the ultrasonic cleaning solves the problem. Only way to know for sure is to reassemble with the current parts.

But then, while not a pain to disassemble, it's not as simple as replacing the RAM.

Any recommendations? Assemble now and test or wait for the new part?

 

[B S Magnet]

UPDATE: I've got the DC-In-Board and System Board in the ultrasonic cleaner now. It'll be done in a few minutes and the next step is to dry it off.

Question: Should I reassemble and try it out? Or wait for the new DC-In-Board to arrive (about a week from now)? I don't mind waiting but I'd be curious to see if the ultrasonic cleaning solves the problem. Only way to know for sure is to reassemble with the current parts.

But then, while not a pain to disassemble, it's not as simple as replacing the RAM.

Any recommendations? Assemble now and test or wait for the new part?

Try it. You needn’t close it all up to test it. Just have the display side resting flush on the table/desk surface and hold up the case from the keyboard side, whilst taking especial care not to touch anything on the board (now facing up and at an angle), and power it up with the present, now cleaned magsafe DC-in board in place. That should be enough to let you know if it’s working or not.

 

[m1maverick]

Try it. You needn’t close it all up to test it. Just have the display side resting flush on the table/desk surface and hold up the case from the keyboard side, whilst taking especial care not to touch anything on the board (now facing up and at an angle), and power it up with the present, now cleaned magsafe DC-in board in place. That should be enough to let you know if it’s working or not.

I went ahead and decided to do a partial reassembly as you suggested. A few things I tried:

• Plugged the DC-In-Board into the power supply to see if the light illuminated. It did not but I have no idea if it would without being connected to the system board.
• Connected the DC-In-Board to the system board and then performed the same test as above with the same results.
• Inserted the system board and DC-In-Board back into the chassis and reconnected most of the cables. A few, such as the speaker and microphone, were left disconnected as I did not feel they would affect the test. I can't say that I connected all the necessary connectors as I didn't do it methodically. Same results as the first two tests.

At this point I decided to wait for the new DC-In-Board to arrive (supposed to be here in a couple of days). Does anyone know if the power adapter light will illuminate under either the first or second bulleted tests I performed?

 

[B S Magnet]

I went ahead and decided to do a partial reassembly as you suggested. A few things I tried:

• Plugged the DC-In-Board into the power supply to see if the light illuminated. It did not but I have no idea if it would without being connected to the system board.
• Connected the DC-In-Board to the system board and then performed the same test as above with the same results.
• Inserted the system board and DC-In-Board back into the chassis and reconnected most of the cables. A few, such as the speaker and microphone, were left disconnected as I did not feel they would affect the test. I can't say that I connected all the necessary connectors as I didn't do it methodically. Same results as the first two tests.

At this point I decided to wait for the new DC-In-Board to arrive (supposed to be here in a couple of days). Does anyone know if the power adapter light will illuminate under either the first or second bulleted tests I performed?

I believe it occurs with the conditions described in the second bullet point: the DC-in board needs to communicate with the logic board for the latter to return to the former the signal needed for displaying a status light on the magsafe adapter.

Although I’m not 100 per cent positive here, that inter-board communication has to happen, since the logic board, not the DC-in board, has a direct connection to the battery (and thus can report to the DC-in board whether or not a battery is detected in its system). Power management itself occurs on the logic board because the logic board needs to know how to clock the system when powered on (for MBs/MBPs/MBAs, this power management system down-clocks the CPU by at least half whenever a battery is not present or when the battery is unable to deliver the current needed to power the system on its own — i.e., a dying/dead battery).

This may be (I’m guessing here) why it takes a moment between when the magsafe adapter makes contact with the DC-in board and when the adapter displays a green (or green, followed by amber) indicator: the power management IC is checking for battery presence/battery health/charge status, before directing the DC-in board on what it should do and what it should display on the adapter.

What you’re doing — trying a different DC-in board — is what I would try first, along with trying a different magsafe adapter (in the unlikely case it itself has a fault somewhere), before moving on to the health of the logic board itself.

 

[Needleroozer]

I believe it occurs with the conditions described in the second bullet point: the DC-in board needs to communicate with the logic board for the latter to return to the former the signal needed for displaying a status light on the magsafe adapter.

Although I’m not 100 per cent positive here, that inter-board communication has to happen, since the logic board, not the DC-in board, has a direct connection to the battery (and thus can report to the DC-in board whether or not a battery is detected in its system). Power management itself occurs on the logic board because the logic board needs to know how to clock the system when powered on (for MBs/MBPs/MBAs, this power management system down-clocks the CPU by at least half whenever a battery is not present or when the battery is unable to deliver the current needed to power the system on its own — i.e., a dying/dead battery).

This may be (I’m guessing here) why it takes a moment between when the magsafe adapter makes contact with the DC-in board and when the adapter displays a green (or green, followed by amber) indicator: the power management IC is checking for battery presence/battery health/charge status, before directing the DC-in board on what it should do and what it should display on the adapter.

What you’re doing — trying a different DC-in board — is what I would try first, along with trying a different magsafe adapter (in the unlikely case it itself has a fault somewhere), before moving on to the health of the logic board itself.

A little more context: the actual MagSafe connector has a simple 1-wire switch chip that runs the LEDs based on commands sent from the motherboard through the DC-In board; the only other data drawn from the MagSafe connector is a 64-bit ID that identifies the charger and gives values like the charger’s max wattage.
A genuine MagSafe adapter will only step up to its full power after the target (i.e. the MacBook) notices it and applies a resistive load. Then the target will read the ID, start charging, and turn the appropriate light on in the connector.

Teardown and exploration of Apple's Magsafe connector

Have you ever wondered what's inside a Mac's Magsafe connector? What controls the light? How does the Mac know what kind of charger it is? T...

www.righto.com

So you do indeed want to have the motherboard connected to the DC-in board and the battery in order for the connector to light up.
(You can even see at the end of that post that he is using a DC-in board as a MagSafe breakout.)

The DC-in board is often the first casualty of water damage on a MacBook, so hopefully it’s the only one at fault here.

 

[m1maverick]

Great information. The DC-In-Board is supposed to arrive tomorrow. Not sure if I'll have the cycles to install it or not.

 

[B S Magnet]

Great information. The DC-In-Board is supposed to arrive tomorrow. Not sure if I'll have the cycles to install it or not.

Good news! Install it when you can install it. We’re patient around here!