SMC Issue on MBP 13 - Hardware Troubleshooting Guide

[Dadioh]

Hi,

thanks a lot for your quick response. I will try that once I'm back in the office. I have no multimeter at home.

How do you know all this stuff? Amazing.

Happy New Year

You are welcome and Happy New Year to you.

Lots of people know this "stuff" and share on this thread. I guess it seems like magic but it is just what you learn in electronics engineering. It's like Lego once you know how the different bits work together

 

[fouroaks]

Hoping does anyone have the schematics for board 820-2936-B this is 13" and is liquid damage and no power this belongs to a friend of mine hoping to fix. Thanks

 

[Leehs]

Re: My last post #2221

I reballed my new SMC chip by hand with fresh leaded solder - What an epic feat! (Well for me anyway)

A massive Thank you to Reason077 and Fteoath64 for resolving the SMC firmware issue I had. I've now got another 100% working MBP under my belt

A Happy New Year to all!

 

[tswartfiguer]

For the magsafe led to go green you need these 3 main signals to be present
PP3V42_G3H - 3.42v U6901 pin#5
SMC_BC_ACOK - 3.2v U6901 Pin#1&2
SYS_ONEWIRE - 3.2v U6900 pin#14

PP3V42_G3H is what's commonly referred to as 'G3 HOT' and can be measured at L6995. The SMC needs to see various signals which spur off PP3V42_G3H. Goto page 46 and you will see that the SMC needs to see 3.42v at various different points, SMC_ONOFF_L,G3_POWERON_L and so on. This is where SYS_ONEWiRE is produced so without those initial signals coming in from PP3V42_GH, the SMC would never produce SYS_ONWIRE.

SMC_BC_ACOK is produced by the charger chip U7000 pin#14 so you need to make sure the voltage supply to the chip is present.

There is an excellent document in this thread somewhere titled 'A1286 power sequence'. I have used this document on numerous occasions to solve magsafe led problems and power on problems. Some of the signal id labels might be slightly different but they still do the same job.

Hello everyone, I have the same logic board as you guys with similar problems, no charging dim light on magsafe etc... I have the schematic but I am having a hard time identifying the chips on the board. On my board it is very hard to read what is printed on them making it almost impossible to fallow and test the same points you guys are testing. Can someone please circle and label where the chips are referenced above (U6901,U6900) I can't seem to find them. Thank you very much to whoever can help me. Also I was able to locate the charger chip and I don't have any voltage to pin 14, does this mean that chip is bad or is something faulty before that point? Thanks in advance for you help.

----------

Hoping does anyone have the schematics for board 820-2936-B this is 13" and is liquid damage and no power this belongs to a friend of mine hoping to fix. Thanks

Look was earlier in this thread I don't remember what page but I know it is poster here somewhere if I find what page I will reply again with a page number.

 

[tswartfiguer]

What do you make of this Dadioh?

You are welcome and Happy New Year to you.

Lots of people know this "stuff" and share on this thread. I guess it seems like magic but it is just what you learn in electronics engineering. It's like Lego once you know how the different bits work together

You seem to be one of the goto guys on here for answers so I was hopping you could help me out and tell me what you make of this picture of my DC in jack pins. I compared it to a picture of another board and it doesn't look right. The history on this board is there was a liquid spill right on the charger area. It still gets 16.9v on pins 1&2 but 3&4 get no voltage and pin 5 gets .01v. I don't know how I would go about fixing this I have a soldering rework station and all the other tools to fix it I just need some advice on how to go about it.

Thanks in advance for yours or anyone else's help or advice.

 

[Wuchi]

Replace the battery. Also how many charge cycles is shown in system report?

new battery inside and it starts up normally. But when magsafe is connected, it says 'not charging' besides battery charging icon. So where to start looking? I have measured many spots and all seems to be working. Only thing where something is odd is when battery is not connected, there is no 12v in the fuse near battery connector.

Help me where to start finding the problem. Also the battery indicator led wire is broken as I mentioned earlier.

edit. hmm I looked coconut battery information and It seems that even though the magsafe is connected and green light is lighted, the MBP is still running on battery. The battery charge is decreasing. So I have measured 16,5volts on logic board in various places but still it does not turn on the MBP without battery and is not charging. Ideas?

edit pt.2 When I take magsafe out the screen gets dimmer and when I connect it, the screen gets bright again.

 

[ZZZAC]

woops

So my 13.3" has gone pretty awfully...rather than testing it i just continued to break it more and more

I had it on my bench testing components when i managed to short the magsafe pins on a screw (yeah, stupid i know) and now its not communicating with the smc.
The fuse is good, someone i know suggested it has damaged the smc chip.

The macbook runs on battery
I tried a new magsafe, whilst a known working battery was plugged in, and the new magsafe adapter diode (transistor on the bottom cought fire). (this only happened when running the dc charge and the battery at the same time though)

i then decided as it was the charging circuit it could wait till ive solved the main issue, and looked at the U7200 chip. i got confused pretty quickly, and off battery this is what i was reading.


8v seems like an odd one, and im just genuinely confused.
am i looking at a dead u7200 and smc here?

and further worse i twice slipped with my meter prongs shorting a 12v cap to a 5v cap and it seemed to smoke around the U2600 usb controller chip.... aswell as kill 5v to 4.0. kill 3.3v completely (still have g3hot) and the second time a slipped it did the same, now it wont react to the power button (i dont think)


now i know at this point i messed up enough in one day to write the board off and i feel pretty bad about it. But to learn something, am i looking at a dead u27200, u2600, and smc chip?

hate screwing up this much in sucha short period of time
cheers guys

 

[kennethf]

macbook pro 2010 15" 820-2850-A

Hi anyone with a working boardview that know the part number on thise ic`s ?
I have boardview for this motherboard but it wont open, gets a message about
"CAN NOT OPEN LANDREX.BRD FILE"

Thanks

 

[iphonerepair12]

Image
In my image i've written what i have measured. With the magsafe (but without the battery) I don't get any 12,5V. 1 leg at around 14,3V/14,4V and the next 2 legs start at 12V but drop gradually in a few minutes to 0,1V.

Seems to me this is not right? Thanks for your help so far.

I also measured the same spots, please see the picture for my measurements (in green). It looks OK to me, but my board is also not powering on (it does have green magsafe light, and sometimes it will charge the battery)

 

[iphonerepair12]

So my 13.3" has gone pretty awfully...rather than testing it i just continued to break it more and more

I had it on my bench testing components when i managed to short the magsafe pins on a screw (yeah, stupid i know) and now its not communicating with the smc.
The fuse is good, someone i know suggested it has damaged the smc chip.

The macbook runs on battery
I tried a new magsafe, whilst a known working battery was plugged in, and the new magsafe adapter diode (transistor on the bottom cought fire). (this only happened when running the dc charge and the battery at the same time though)

i then decided as it was the charging circuit it could wait till ive solved the main issue, and looked at the U7200 chip. i got confused pretty quickly, and off battery this is what i was reading.


8v seems like an odd one, and im just genuinely confused.
am i looking at a dead u7200 and smc here?

Image


and further worse i twice slipped with my meter prongs shorting a 12v cap to a 5v cap and it seemed to smoke around the U2600 usb controller chip.... aswell as kill 5v to 4.0. kill 3.3v completely (still have g3hot) and the second time a slipped it did the same, now it wont react to the power button (i dont think)


now i know at this point i messed up enough in one day to write the board off and i feel pretty bad about it. But to learn something, am i looking at a dead u27200, u2600, and smc chip?

hate screwing up this much in sucha short period of time
cheers guys

I have done the same measurement on my board, and I think I found out the the ISL6259 is dead... Can someone confirm? or are there other things I have to check first before replacing this IC? You can find my measurement in the picture (I wrote them in green)

(It is a water damaged K90i logic board, with green light on magsafe)

 

[Wuchi]

new battery inside and it starts up normally. But when magsafe is connected, it says 'not charging' besides battery charging icon. So where to start looking? I have measured many spots and all seems to be working. Only thing where something is odd is when battery is not connected, there is no 12v in the fuse near battery connector.

Help me where to start finding the problem. Also the battery indicator led wire is broken as I mentioned earlier.

edit. hmm I looked coconut battery information and It seems that even though the magsafe is connected and green light is lighted, the MBP is still running on battery. The battery charge is decreasing. So I have measured 16,5volts on logic board in various places but still it does not turn on the MBP without battery and is not charging. Ideas?

edit pt.2 When I take magsafe out the screen gets dimmer and when I connect it, the screen gets bright again.

I noticed that when mbp is on I pull the magsafe off and put it back in the mbp is charging for a 30 seconds. Coconut battery says it is charging and the battery charge icon turns to charging icon for the same time. but it goes back to not charging.

Is mbp using the battery all the time, and only charging it when magsafe is connected? It doesn't run just with magsafe?

 

[coco666]

I have done the same measurement on my board, and I think I found out the the ISL6259 is dead... Can someone confirm? or are there other things I have to check first before replacing this IC? You can find my measurement in the picture (I wrote them in green)

(It is a water damaged K90i logic board, with green light on magsafe)
Image

Please check PP3V42_G3H, because I think you don't have this voltage

 

[cmdrdata]

Please check PP3V42_G3H, because I think you don't have this voltage

Wrong analysis. If the magsafe LED lights up green or orange, that means that SMC is able to communicate with the magsafe (the ONEWIRE signal is normally 3.4v because of a pull up to G3HOT). If G3HOT was bad, this line will be near 0v and thus neither SMC or magsafe can pass status via serial communication pulse signals. SMC is alive also because it is powered by G3HOT (chip pins B1, M1, H10). Note that when you connect the magsafe, it initially stays off, then after a few seconds it goes green then orange if the battery is present and needs charging. That delay is the status exchange between magsafe and SMC.

 

[iphonerepair12]

Wrong analysis. If the magsafe LED lights up green or orange, that means that SMC is able to communicate with the magsafe (the ONEWIRE signal is normally 3.4v because of a pull up to G3HOT). If G3HOT was bad, this line will be near 0v and thus neither SMC or magsafe can pass status via serial communication pulse signals. SMC is alive also because it is powered by G3HOT (chip pins B1, M1, H10). Note that when you connect the magsafe, it initially stays off, then after a few seconds it goes green then orange if the battery is present and needs charging. That delay is the status exchange between magsafe and SMC.

Yes, G3HOT is present so the SMC should be OK.

 

[cmdrdata]

I noticed that when mbp is on I pull the magsafe off and put it back in the mbp is charging for a 30 seconds. Coconut battery says it is charging and the battery charge icon turns to charging icon for the same time. but it goes back to not charging.

Is mbp using the battery all the time, and only charging it when magsafe is connected? It doesn't run just with magsafe?

I have forgotten the state of your system at this time after all the replacement of parts to get where it is now.

In general, on a good working MBPs (or MBs for that matter) run from AC/magsafe power when it is plugged in. even when battery is plugged in and detected by the Mac.
When the battery needs a charge as detected by the SMC, ithe SMC will enable the charger IC (6258 or 6259) to begin charging the battery and the SMC will turn magsafe led to orange.
When the battary reports full charge to the SMC, the charger IC is turned off by the SMC and green led turned on. There is also one power FET (on K90i is Q7055) that will be turned off, thus no battery is consumed except the small amount of power that goes to the G3HOT diode pair (on K901 this is D6990).
When magsafe is disconnected and battery is good, the SMC will be alive if G3HOT is present (remember D6990 gets direct battery power too). When MBP is powered on, Q7055 is enabled thus allowing battery power to be available for system power. The charger circuit will be turned off as it is not needed.

 

[dieett]

Boarview K18

Hi anyone with a working boardview that know the part number on thise ic`s ?
I have boardview for this motherboard but it wont open, gets a message about
"CAN NOT OPEN LANDREX.BRD FILE"

Thanks

here the board View file. I have also inserted the associated program.

Good Luck!

 

[iphonerepair12]

I am already a step closer to the solution for my K90i logic board with liquid damage. I did some measurement around U7200 and i did not got any voltage there, then I measured C6603 and found out it was shorted. (12.3ohm) so I took it off but the pads are still shorted. I suspect that the short is on PP5V_3S. Can somebody help me tracing the short? There are so many components connected to PP5V_3S that I do not know where to start.

 

[Dadioh]

You seem to be one of the goto guys on here for answers so I was hopping you could help me out and tell me what you make of this picture of my DC in jack pins. I compared it to a picture of another board and it doesn't look right. The history on this board is there was a liquid spill right on the charger area. It still gets 16.9v on pins 1&2 but 3&4 get no voltage and pin 5 gets .01v. I don't know how I would go about fixing this I have a soldering rework station and all the other tools to fix it I just need some advice on how to go about it.

Thanks in advance for yours or anyone else's help or advice.

Pins 3 and 4 are ground so they should be 0V. Pin 5 should be about 3V if the communication is happening with the SMC. Check pin 14 of the ISL6258 charger chip.

 

[triplelucky]

I am already a step closer to the solution for my K90i logic board with liquid damage. I did some measurement around U7200 and i did not got any voltage there, then I measured C6603 and found out it was shorted. (12.3ohm) so I took it off but the pads are still shorted. I suspect that the short is on PP5V_3S. Can somebody help me tracing the short? There are so many components connected to PP5V_3S that I do not know where to start.

I think you'll need to figure out where your missing S5 voltages are on U 7200 prior to troubleshooting the S3 voltages.

 

[iphonerepair12]

I think you'll need to figure out where your missing S5 voltages are on U 7200 prior to troubleshooting the S3 voltages.

Thanks for the tip! I just measured P5V_S5 everywhere 0V on the board. I also noticed that it does have a short with GND of 12.5ohm. The next step will be looking at this short? And how to start? just taking off each component which is connected to P5V_S5 and see if the short is gone?

 

[triplelucky]

There is a document you can find by searching the thread that explains the power on sequences and what voltages come up at what sequence. It is translated from Chinese and a little hard to read. If you study the progression of voltages and sequences as they come up in order you might find it helpful in your troubleshooting.

Since you have no voltages at all on U7200 you could drop back and work through your rail voltages from the beginning starting with the stand by voltages.

Where is the last place in the power on sequence that you are seeing correct voltages?

 

[iphonerepair12]

There is a document you can find by searching the thread that explains the power on sequences and what voltages come up at what sequence. It is translated from Chinese and a little hard to read. If you study the progression of voltages and sequences as they come up in order you might find it helpful in your troubleshooting.

Since you have no voltages at all on U7200 you could drop back and work through your rail voltages from the beginning starting with the stand by voltages.

Where is the last place in the power on sequence that you are seeing correct voltages?

I found the link http://www.filesnack.com/files/cdc8wcpz it is for A1286 but I think that would be almost the same?

I will go testing tomorrow and will let you know at which point I do not get the correct voltages.

 

[tswartfiguer]

Pins 3 and 4 are ground so they should be 0V. Pin 5 should be about 3V if the communication is happening with the SMC. Check pin 14 of the ISL6258 charger chip.

Pin 14 doesn't have any voltage at all. I ordered some resistors and the max9940 chip "U6900" I noticed I had no continuity between "R6929 pin 1 and U6900 Pin 1. Do you think this might be the reason I don't get a charging idicator light on my magsafe and the battery don't charge.

Also the resistor right before U6900 was missing completely it doesn't show up on my schematic but it shows up as a 100k 5% 1/16 MF/LF 0420 resistor on my board viewer. I ordered that as well. Is any of this making sense to you or am I on the wrong track?

 

[WubboZ]

I'm still fascinated by this thread, so much knowledge!
I do have small question to which you guys probably know the answer. I have some problems with the USB on my MBA 2.1. It was working just fine, but a couple of months ago the keyboard an trackpad would freeze up leaving no other option than to reset. I believe I tried an external mouse, which worked at the time. I haven't used the MacBook in a while now, but I decided to try an fix it again (the new year and all...), but it appears USB is completely dead now: keyboard, trackpad, USB port, nothing. Booting also takes forever despite the SSD, it hangs minutes at the 'gray screen of death' before showing the apple logo an continuing.
So far I have concluded that the USB port does supply 5V, but even a keyboard isn't recognized.
Disconnection all non essential items from the logic board keeping just the screen, MagSafe and keyboard or USB port cable still results in non responsive keyboard (both USB and internal).
Usually I'd go for SMC reset and NVRAM reset, but these don't seem to work (because the keyboard doesn't work, dohh).
Does anyone have an idea to reset the SMC without keyboard, or suggestions what else to try or check?
I'm puzzled... Could it be a dead USB controller?

 

[dellxps15]

after a while i was able to change and solder the u7000 i625 qfn chip, but now i have a volt drop on DC or AC in . it pass from 16v to lower as 1.5 or going to 0.

is that some problem with other component or maybe my i625 is bad ? (i have stressed it a bit because was not able to solder it properly as it was my first qfn chip.

any suggestion would be appreciated. pin 14 of u7000 is 3.36volt.