SMC Issue on MBP 13 - Hardware Troubleshooting Guide

[U-234]

Do you have a known god battery? If yes, try that.
As I understand it, SMC is the MASTER, so it sends a read status to the battery asking for a response and battery status. If it gets "I am near death code", the SMC reports a "Replace Battery Soon" message that gets displayed on your desktop battery icon. If the SMC doesn't get any response from the battery or battery is in shutdown or self protective mode, it displays an "X" on the battery icon. The ISL625x is also a SLAVE to SMC, so it receives charging directives from the SMC based upon battery charge status that the SMC gets from the battery itself. See the attached block diagram for A1278 (logic board version M97A, early 2009).

I have two good known batteries, tried both with the same results. Now, however it appears I have a new problem. I decided to remove the ISL again and solder it more precisely since I did that now on the battery fuse and battery connector pins 10, 11, 12 i'm getting 0V. On the DCIN fuse i'm getting 17V which is fine. I still get 3.4 on G3hot which is good but because i'm getting 0V on the main fuse now the board won't power on. I tried both with megsafe and battery. I checked the fuse and getting 1 Ohm which means it is fine. Not sure if i shorted something during second install or what. How critical is ISL6259A? Does the main function is charging the battery or also power supply? In another words if it got removed or damaged more (e.g. overheat) will it effect 12V on the main fuse?

If ISL6259 doesn't effect our 12V fuse than what should check now?

 

[U-234]

Good news: I got my MBP late 2009 working again. Magsafe power works, battery power works, separately or together. Sadly, in the process of putting the logic board back into the unibody, the battery indicator flex cable broke off, so that piece is now on order (922-0828-A). Afterwards, I attempted to upgrade the OS to Snow Leopard, but alas, it seemed that the superdrive is also defective. It was unable to read the OS disk. I heard the disk spin, then it spits it out. So that too will need to be looked into, a task for another day.

I have another mac with the same issue as you have - the superdrive spins the disk for few second and then spits it out. I took it apart and cleaned the laser with ISA, i'm testing out while the whole drive is disassembled so I see the machanism just in case something is stuck. But nothing machanicaly seems to be wrong. The laser slides down on two rods...tries to read and after 5 second the laser slides up on the rods and spits the disk. Not sure if there is anything I can do fix it or getting a new one is the only option.
Were you able to fix yours?

 

[cmdrdata]

I have another mac with the same issue as you have - the superdrive spins the disk for few second and then spits it out. I took it apart and cleaned the laser with ISA, i'm testing out while the whole drive is disassembled so I see the machanism just in case something is stuck. But nothing machanicaly seems to be wrong. The laser slides down on two rods...tries to read and after 5 second the laser slides up on the rods and spits the disk. Not sure if there is anything I can do fix it or getting a new one is the only option.
Were you able to fix yours?

I bought a NEW unit from eBay and did not bother fixing mine. I didn't want the chance of buying a used one and later find out it has problems (have had that experience on an older Macbook).

 

[mac-n-sauce]

Wanted to post some info that might help.
I have a 2010 MBP 15" i7 2.66GHz
Would only power from a good battery.
Would not charge battery or work on charger.
Sent it out for repair. I am attaching photos of what was repaired.
It seems that an internal trace was bad from how they repaired it, but I am learning all this so I can not be sure. I would like to here your opinions.
Thanks.

Also, does anyone have a layout for the ISL9504B 48 pin chip. I have a 2010 13" MBP with not lights on magsafe, no charge no power G3Hot is 1.15v

 

[NicoNL]

13 inch A1278 unibody charger not recognized

After repairing the backlight (current sense resistors were open circuit), I could still only start in debug-mode, i.e. with a SMC-reset.

I found that the battery was (too) empty and charged it thru a common 19V-adapter (with resistors of course).

After doing so, every thing worked fine, apart from that the macbook was not charging. Looking in the system it appeared that the charger was not recognized. Changing the DC-board and/or the power brick didn't resolve the issue. I read a while in this thread and came across the overvoltage-circuit of a Pro 13.
I found the double mosfet switch in the one wire to the middle pin of the magsafe on my board, and concluded that the gates were not driven, so the middle pin of the magsafe was not "connected" to the SMC-circuitry.

Then I found the LM397 and it worked allright. So then I went looking for the two mosfets connected to the Vs and the output of the LM397. I beeped for half an hour thru the logic board but could not find either of them!!!

Is there someone who can enlighten me? Or has a schematic of the A1287 unibody? (Does the overvoltage circuit work in the same way as in the Pro?)

Many thanks in advance!!!

PS: I'm thinking of just connecting the two drains of the double mosfet, so that the overvoltage circuit will be "bypassed". That way I must be able to charge and to light the Magsafe led? I suppose I can just do so?

 

[NicoNL]

Update: I just found the equivalent of Q6915 (of the 1 wire over voltage protection circuit of the Pro 13") on my board. Two resistors (R6915 and R6917) are open circuit and between R6917 and a via 2mm ahead the copper has just completely gone. It just explains what I measured before.

Update 2: BUMMER. I now have 6.8V on the gates of the one wire switch mosfets, and 3.4V on the middle pin, but still my charger is not recognized and the unit won't charge. Now the led of the magsafe is glowing (very dim) green. Anyone advice?

Update 3: It appears that it is charging very slowly. I believe ther is something written about that in this thread...

 

[cmdrdata]

Update: I just found the equivalent of Q6915 (of the 1 wire over voltage protection circuit of the Pro 13") on my board. Two resistors (R6915 and R6917) are open circuit and between R6917 and a via 2mm ahead the copper has just completely gone. It just explains what I measured before.

Update 2: BUMMER. I now have 6.8V on the gates of the one wire switch mosfets, and 3.4V on the middle pin, but still my charger is not recognized and the unit won't charge. Now the led of the magsafe is glowing (very dim) green. Anyone advice?

Update 3: It appears that it is charging very slowly. I believe ther is something written about that in this thread...

There are so many A1278 versions and logic boards, it is hard to figure out what you are seeing/measuring in your comment. It would help if you post the relevant schematic with annotation of voltages measured, then the community here can at least get an idea what problem you are describing.

 

[mac-n-sauce]

After repairing the backlight (current sense resistors were open circuit), I could still only start in debug-mode, i.e. with a SMC-reset.

I found that the battery was (too) empty and charged it thru a common 19V-adapter (with resistors of course).

After doing so, every thing worked fine, apart from that the macbook was not charging. Looking in the system it appeared that the charger was not recognized. Changing the DC-board and/or the power brick didn't resolve the issue. I read a while in this thread and came across the overvoltage-circuit of a Pro 13.
I found the double mosfet switch in the one wire to the middle pin of the magsafe on my board, and concluded that the gates were not driven, so the middle pin of the magsafe was not "connected" to the SMC-circuitry.

Then I found the LM397 and it worked allright. So then I went looking for the two mosfets connected to the Vs and the output of the LM397. I beeped for half an hour thru the logic board but could not find either of them!!!

Is there someone who can enlighten me? Or has a schematic of the A1287 unibody? (Does the overvoltage circuit work in the same way as in the Pro?)

Many thanks in advance!!!

PS: I'm thinking of just connecting the two drains of the double mosfet, so that the overvoltage circuit will be "bypassed". That way I must be able to charge and to light the Magsafe led? I suppose I can just do so?

What year is the MBP 13"

 

[NicoNL]

There are so many A1278 versions and logic boards, it is hard to figure out what you are seeing/measuring in your comment. It would help if you post the relevant schematic with annotation of voltages measured, then the community here can at least get an idea what problem you are describing.

I have a late 2008 (MB466N/A) unibody 2Ghz 13".
I don't have a schematic.

I just looked at the schematic of the voltage protection circuit of the pro 13" in this thread and then I found some of the corresponding parts on my board. I replace two resistors and fixed a broken lane.
Now the voltage protecting circuit is working, it lets pass the one wire signal from the MagSafe to the SMC-circuit.

Now I have a (very) dim green led an a very slow charging battery.
Also there's 3.42 V on the middle pin of the magsafe connector. Every now and then there's a dip to ground (tested with an oscilloscope).

The system boots and runs on battery as well as on the power brick. (It's just switching to the power brick when you connect it.)

But the power brick is still not identified in the system properties.
So I think the signal from the magsafe still does not reach the SMC-chip (in a proper way). Because of that the SMC-chip also won't enable the charging-ic to (normal) charge.

I actually want to know were the one wire signal is going to after it went thru the double mosfet switch.
It has it's pull up to 3.42V working now, it becomes low now and then, so why isn't it working?

 

[mac-n-sauce]

I have a late 2008 (MB466N/A) unibody 2Ghz 13".
I don't have a schematic.

I just looked at the schematic of the voltage protection circuit of the pro 13" in this thread and then I found some of the corresponding parts on my board. I replace two resistors and fixed a broken lane.
Now the voltage protecting circuit is working, it lets pass the one wire signal from the MagSafe to the SMC-circuit.

Now I have a (very) dim green led an a very slow charging battery.
Also there's 3.42 V on the middle pin of the magsafe connector. Every now and then there's a dip to ground (tested with an oscilloscope).

The system boots and runs on battery as well as on the power brick. (It's just switching to the power brick when you connect it.)

But the power brick is still not identified in the system properties.
So I think the signal from the magsafe still does not reach the SMC-chip (in a proper way). Because of that the SMC-chip also won't enable the charging-ic to (normal) charge.

I actually want to know were the one wire signal is going to after it went thru the double mosfet switch.
It has it's pull up to 3.42V working now, it becomes low now and then, so why isn't it working?

Here is the schematic i believe:Try page 58. This should be similar to yours if it is not identical.

 

[mac-n-sauce]

Actually here is a link to your specific MBP
http://www.scribd.com/doc/87386781/Apple-Macbook-a1181-k36c-Mlb-Schematic

it shows the items your are looking for. The one I sent is similar, but a little different.

 

[NicoNL]

Actually here is a link to your specific MBP
http://www.scribd.com/doc/87386781/Apple-Macbook-a1181-k36c-Mlb-Schematic

it shows the items your are looking for. The one I sent is similar, but a little different.

This is an A1181, I have A1278.
Couldn't find Magsafe or SYS_ONEWIRE on it.
But thanks anyway!

I did find it on the A1286 Pro schematic.

And the SYS_ONEWIRE is there only connected to a 2k pull up resistor to PP3V3_S5_SMC and to the F2117 (SMC-ic).

So now I'm really wondering: If I have a good working DC_IN-board, a good working MagSafe-connector, if I have 3.4V on the middle pin and SYS_ONEWIRE, if this pin every now and then seems to be pulled low, why doesn't it work? Why can't the SMC identify the charger (and following, why doesn't it permit charging?).

I have two white A1184 60W magsafe-chargers, one came with this macbook, and both can charge the battery of a 2010 pro 13". The same for two DC_in boards.

PS: I read the first 8 pages of this thread and saw some other people having (partly) the same problem, ie a dim green led, very slow charging, and no identification of the charger. Till now I didn't read the solution, is it ever solved?
(The nasty thing seems that there are very many similar, but not exactly the same problems...)

 

[NicoNL]

SOLVED!!

After comparing the SYS_ONEWIRE and the middle pin of the MagSafe I saw that the former was pulled to zero about one time in 5 seconds and the latter every second!

So, at first I thought that the bilateral switch wasn't that bilateral after all....

But that was a too exotic thought. It was just BOTH dc-in-boards that were ruined thru the proces of experimenting. There is a series resistor in the sense-wire to the middle pin. I measured 15kohm at the one I was using and 300-450 on the other, but after messing around a bit the latter became 100 (resistor was apparently broken).
On yet another model DC-in board (does not fit in this macbook) there were two series resistors, of both 22 ohm (and an inductor in between).
I thought 100 ohm would be a reasonable guess, so I put two 100 ohm resistors at the DC-in boards and now I have a working macbook!!!

Anyways, I had allready learned that there can be quite big sparks at the DC-in board. This must be because the mass-connection between the DC-in board and the motherboard is THRU the aluminium casing!!

You must put in at least one screw in both the DC-in board and the logic board to prevent sparks!!! And apparently they can not only blew the safety diode on the dc-in board but also the resistors in the sense-line.
I think many, many DC-in boards have been wrecked because of not fastening these screws. (But maybe I'm not telling something new, I just haven't read it yet.)

Thanx anyone for helping me around!

 

[mac-n-sauce]

SOLVED!!

After comparing the SYS_ONEWIRE and the middle pin of the MagSafe I saw that the former was pulled to zero about one time in 5 seconds and the latter every second!

So, at first I thought that the bilateral switch wasn't that bilateral after all....

But that was a too exotic thought. It was just BOTH dc-in-boards that were ruined thru the proces of experimenting. There is a series resistor in the sense-wire to the middle pin. I measured 15kohm at the one I was using and 300-450 on the other, but after messing around a bit the latter became 100 (resistor was apparently broken).
On yet another model DC-in board (does not fit in this macbook) there were two series resistors, of both 22 ohm (and an inductor in between).
I thought 100 ohm would be a reasonable guess, so I put two 100 ohm resistors at the DC-in boards and now I have a working macbook!!!

Anyways, I had allready learned that there can be quite big sparks at the DC-in board. This must be because the mass-connection between the DC-in board and the motherboard is THRU the aluminium casing!!

You must put in at least one screw in both the DC-in board and the logic board to prevent sparks!!! And apparently they can not only blew the safety diode on the dc-in board but also the resistors in the sense-line.
I think many, many DC-in boards have been wrecked because of not fastening these screws. (But maybe I'm not telling something new, I just haven't read it yet.)

Thanx anyone for helping me around!

Just in case I believe this is your actual version and your info is on page 57

 

[Dadioh]

SOLVED!!

Anyways, I had allready learned that there can be quite big sparks at the DC-in board. This must be because the mass-connection between the DC-in board and the motherboard is THRU the aluminium casing!!

You must put in at least one screw in both the DC-in board and the logic board to prevent sparks!!! And apparently they can not only blew the safety diode on the dc-in board but also the resistors in the sense-line.
I think many, many DC-in boards have been wrecked because of not fastening these screws. (But maybe I'm not telling something new, I just haven't read it yet.)

Thanx anyone for helping me around!

I frequently use a DC-in board outside of the case to power logic boards that I am working on so you do not require the ground to be connected for it to work. The 18v is carried on 2 pins, the return is carried on 2 pins, and the sense is on the middle. There may be some protection diodes running off 18v to chassis ground but those are just for transient protection.

The thing that you do need to be careful with when using a loose DCin board is to align the pins when connecting it. The casing of the MacBook normally does this alignment but without the case you need to be careful.

 

[cmdrdata]

I frequently use a DC-in board outside of the case to power logic boards that I am working on so you do not require the ground to be connected for it to work. The 18v is carried on 2 pins, the return is carried on 2 pins, and the sense is on the middle. There may be some protection diodes running off 18v to chassis ground but those are just for transient protection.

The thing that you do need to be careful with when using a loose DCin board is to align the pins when connecting it. The casing of the MacBook normally does this alignment but without the case you need to be careful.

First, nice work NicoNL. Yes, dadioh is correct. I have powered bare logic board with DCIN board just plugged in to magsafe and logic board without securing it anywhere and it works just fine. I think the spark may have been caused by the fact that Apple in their "infinite wisdom" CHANGED the pin out alignment.

On the magsafe (plug and DCIN side) connector pins 1/5 is ground, 2/4 is +V, and pin 3 is adapter sense line.

On the DCIN to logic board connector, the power pins are re-arranged, and
pins 1/2 is +V, 3/4 is ground, and pin 5 is adapter sense.

 

[kamils007]

Macbook A1260 only "bypass SMC"

Welcome.
Sorry for my poor English;-))
Macbook Pro 15 "A1260. The battery is operating normally. Macbook recognizes and charges the battery. Only one power supply, start only "bypass SMC" What could be the scope of damage? Is it only the SMC, or ICH8?
What to look for?
Regards Kamil.

 

[NicoNL]

The thing that you do need to be careful with when using a loose DCin board is to align the pins when connecting it. The casing of the MacBook normally does this alignment but without the case you need to be careful.

Hmmz. Maybe I jumped to conclusion too fast.
After I had sparks and blew up the protection diode I just draw (reverse engineered) the schematics of the DC-in board and saw that the mass connection was floating, i.e mass was not connected with 0v (return line). Only on the logic board mass is connected to 0v.

Then I stopped thinking and tightened the screws of the DC-in board and the logic board. Then I had no sparks anymore.
But.... as you say, the sparks apparently were because of bad aligning and that was also resolved by tightening the screws... (or because of bad aligning AND a floating mass?)

Unfortunately I failed at that point to see that the resistors of the DC-in board were also ruined, which costed me a considerable amount of time later on. This (failing-mechanism) is actually still a bit of a mystery...

Anyways, I allready sold that macbook two hours ago, so for the moment I stop thinking about that...

 

[Dadioh]

I frequently use a DC-in board outside of the case to power logic boards that I am working on so you do not require the ground to be connected for it to work. The 18v is carried on 2 pins, the return is carried on 2 pins, and the sense is on the middle. There may be some protection diodes running off 18v to chassis ground but those are just for transient protection.

The thing that you do need to be careful with when using a loose DCin board is to align the pins when connecting it. The casing of the MacBook normally does this alignment but without the case you need to be careful.

And if you do use a DC-in board out of the case then it is a really really good idea to give it a wrap of Kapton tape so that if it gets tugged around and touches the logic board you don't get 18v going places it shouldn't letting out smoke that it shouldn't. Not that this is the voice of experience speaking or anything

 

[James1511]

I read most of the thread and everything tests out okay voltage wise. I had a green charging light the whole time, and the charge indicator worked, but the computer was dead. I have it narrowed to a bad power button, I think. I grounded pin 5 on the keypad and it boots to the white apple screen, but then shuts off before getting anywhere. The superdrive is making noise and doesn't seem to be booting the osx cd. I'm not sure if that is bad as well.
My question is do I need to buy a whole keyboard, upper case or can I find a power button somewhere? Or is it the ribbon? Can you guys LMK what the definitive fix for this is, I would love to have my computer back!

 

[Dadioh]

I read most of the thread and everything tests out okay voltage wise. I had a green charging light the whole time, and the charge indicator worked, but the computer was dead. I have it narrowed to a bad power button, I think. I grounded pin 5 on the keypad and it boots to the white apple screen, but then shuts off before getting anywhere. The superdrive is making noise and doesn't seem to be booting the osx cd. I'm not sure if that is bad as well.
My question is do I need to buy a whole keyboard, upper case or can I find a power button somewhere? Or is it the ribbon? Can you guys LMK what the definitive fix for this is, I would love to have my computer back!

The power switch is a metallic disk that is permanently attached to the ribbon cable leading to the keyboard so you can't replace just the switch. However, if you remove the 2 tiiiiiny screws that fasten the switch assembly to the base of the macbook you might be able to examine it to see if it just needs to be cleaned. There is a small circular spring so don't lose that. Try scrubbing down the disk and the contact area on the ribbon cable to see if it is just a bad contact due to corrosion. Worth a shot anyway.

You can replace just the keyboard/switch combo. You can find keyboards on eBay. There are approximately half a kajillion tiny screws holding the keyboard onto the base so get yourself a decent quality 00 philips screwdriver and take your time.

Good luck

 

[James1511]

Much appreciated Dadioh, you're a lifesaver!

 

[jugger18]

The power switch is a metallic disk that is permanently attached to the ribbon cable leading to the keyboard so you can't replace just the switch. However, if you remove the 2 tiiiiiny screws that fasten the switch assembly to the base of the macbook you might be able to examine it to see if it just needs to be cleaned. There is a small circular spring so don't lose that. Try scrubbing down the disk and the contact area on the ribbon cable to see if it is just a bad contact due to corrosion. Worth a shot anyway.

You can replace just the keyboard/switch combo. You can find keyboards on eBay. There are approximately half a kajillion tiny screws holding the keyboard onto the base so get yourself a decent quality 00 philips screwdriver and take your time.

Good luck

I have fixed a few macbook unibody a1342 (white model). One of the things they also have is a rubberized bottom. Apple had issues with the rubber coming off the metal plate and you can send in the old one for a new one. It also comes with new screws and an awesome phillips screwdriver. I use it for all my appled repairs (macbooks, ipods, iphones)

 

[SellYourMacBook]

2012 13" MacBook Pro not charging

Hi everyone,

I have spilled a tiny amount of water on my 2012 13" macbook pro. i took every precaution and cleaned/dried logic board. it now runs off the battery but will not charge. It will not run off just the power cord. if i do a smc reset it will charge the battery but if i press power it will turn on and light on magsafe will switch back to green and not charge. can you guys help me see whats causing it now to charge battery? everything works except wont charge. i hear some kind of noise when i put a dead battery in and it struggles to charge, magsafe light switches from green to amber continuously.

ifixit doesnt have pictures of logic board of 2012 model so maybe you guys will be interested in seeing the difference.

if you PM me i can send high resolution pics of the logic board.

thanks in advanced !! this thread is very interesting !

 

[mark!]

delete