SMC Issue on MBP 13 - Hardware Troubleshooting Guide

[funtotos]

Have 3.50 power pads
Fuse ok
No water damage .

Thks

i find a component that burns C7540 PPBUS_S5_HS_COMPUTING_ISNS

C7540 burn when i plug magsafe

I replace components ?

thanks you

 

[funtotos]

i find a component that burns C7540 PPBUS_S5_HS_COMPUTING_ISNSImage
C7540 burn when i plug magsafe

I replace components ?

thanks you

I replace the component. C7540
everything works

thanks you

 

[texynz]

Interestingly Dadioh, I have just checked the firewire port and it is not shown in the system info either as a device. I dont have a firewire device to try, but I suspect if it is like the other two devices it is also "offline"

Dadioh did you have a copy of the schematic you could send me? Obviously there is an issue in the PCI bus area

 

[zeroozzy]

Problems on my macbook

Guys I'm in trouble , my macbook get the white screen , only the led lcd on, the more the image does not appear, dismounted and saw a problem next to the LCD connector on the motherboard. My macbook a1278 I7 and realized the problems that had occurred. Anyone with any solution to my problem . I am Brazilian computer technician , but never went behind to solve this problem

Thank You

 

[Dadioh]

Guys I'm in trouble , my macbook get the white screen , only the led lcd on, the more the image does not appear, dismounted and saw a problem next to the LCD connector on the motherboard. My macbook a1278 I7 and realized the problems that had occurred. Anyone with any solution to my problem . I am Brazilian computer technician , but never went behind to solve this problem

Thank You

Yeah. Looks like you shorted out the 3.3V that feeds the LCD screen. The ferrite bead (filter) has been vaporized. You will need to replace it with some creative soldering.

 

[Monkeywrap]

Hi!

I have a 15" MBP A1286 mid 2010 i5 2.4GHz that died suddenly while on battery. After that the laptop doesn't boot or charge battery. Magsafe has only green led on. SMC reset does nothing and LB part number is 820-8250-A.

G3Hot measured 3.38V with and without battery. U7000 pin14 showing 3,20V with Magsafe. Magsafe board seems to be OK. Haven't tested with known good battery as I don't have spare.

I also measured U7000 pins 21 and 24 with battery and magsafe connected.

pin 21 LGATE shows 0.56V
pin 24 UGATE shows 13.35V

Battery connector pins 1-3 fluctuate between 4V-8V, pins 4 and 6 between 3.14V-3.38V, pin 5 0.01-0.03V


Any thoughts of this?

ps. also attached picture showing U6900 and U6901 voltages while battery and magsafe connected.

 

[Dadioh]

Hi!

I have a 15" MBP A1286 mid 2010 i5 2.4GHz that died suddenly while on battery. After that the laptop doesn't boot or charge battery. Magsafe has only green led on. SMC reset does nothing and LB part number is 820-8250-A.

G3Hot measured 3.38V with and without battery. U7000 pin14 showing 3,20V with Magsafe. Magsafe board seems to be OK. Haven't tested with known good battery as I don't have spare.

I also measured U7000 pins 21 and 24 with battery and magsafe connected.

pin 21 LGATE shows 0.56V
pin 24 UGATE shows 13.35V

Battery connector pins 1-3 fluctuate between 4V-8V, pins 4 and 6 between 3.14V-3.38V, pin 5 0.01-0.03V


Any thoughts of this?

ps. also attached picture showing U6900 and U6901 voltages while battery and magsafe connected.

Starting point is to try with a good battery. You could spend a lot of time troubleshooting the ISL6259 (U7000) circuit when a battery replacement is all that is required.

A quick check is to unplug the battery and plug in the magsafe. Then measure what you are getting out of the ISL6259. Easiest place to check is on the white fuse near the device. It should be about 12.5V. If not, then there is something wrong with the charge circuit.

 

[Monkeywrap]

Starting point is to try with a good battery. You could spend a lot of time troubleshooting the ISL6259 (U7000) circuit when a battery replacement is all that is required.

A quick check is to unplug the battery and plug in the magsafe. Then measure what you are getting out of the ISL6259. Easiest place to check is on the white fuse near the device. It should be about 12.5V. If not, then there is something wrong with the charge circuit.

Measured the white fuse and it shows 12.53V but when I measured it again, it shows 12.53V but then drops to about 2.5V and back to 12.53V.

And sometimes Magsafe connector light doesn't light up at all and then the white fuse is measured steady 12.53V.

 

[Dadioh]

Measured the white fuse and it shows 12.53V but when I measured it again, it shows 12.53V but then drops to about 2.5V and back to 12.53V.

And sometimes Magsafe connector light doesn't light up at all and then the white fuse is measured steady 12.53V.

Should stay solid at 12.5V. If it is dropping off then there is something in the charge circuit that is detecting a fault and "hiccuping".

With power off test the resistances of the surrounding circuitry. Particularly sense resistors. Also, measure the resistance between each pin and ground of the ISL6259 charger. The typical measurements can be found somewhere in the thread.

 

[d.liu]

Hey guys I had problems with my A1278 logic board and I now have good news. I was lucky enough as I noticed the inductor in the one wire circuit fell off.

After asking for help and getting an inductor from Dadioh I managed to solder it on and guess what, green charging light is on!

So now I've got myself the same MacBook pro back and I just want to say thank you to everyone that still contribute to this topic. You are all very kind!

Cheers!

 

[MohavePC]

MBP a1278 not powering on.

Hello all:
I have been studying this thread in hopes of repairing my MBP rather than replacing the LB
I have a MBP a1278 MLB # C02249601R9F1YK10
O have tried the SMC bypass with no luck. I have 17.5v on the magsafe pins with charger attached. the Battery shows full with the leds on the side. the switch bypass shows 3.6v and responds by dropping to .5v when PO switch is pressed. All white fuses show 13.5v with out any fluctuation, With or without battery and magsafe plugged in. No apparent moisture (bought used and worked for 6 months) or signs of spillage anywhere. No signs of shorting. I was told by Mac repair in Phoenix that if the battery indicator lights are functioning that the Logic Board is most likely ok. Is this true?

I am extremely tech savvy and have no qualms replacing most components. My only issue is that after going through this thread and trying the tests suggested I am more confused. by all rights this machine should boot without issue.

 

[macelek01]

A1286 turns on and after turns off

Hy Everybody!

I would like to ask some help in measuring. I have a faulty mbp logic board. It is a 820-2915-b (15”, 2011 early, 2.0Ghz).
The board turns on, but about 2 seconds turns off. If I press the power bottom the sleep led flashing one, the fans spin up, and after the board turns off.

I tried the smc reset, and start without smc, but the situation same as previously.

Can somebody give me idea how I can look for the issue? What should be measured?

Thanks a lot.

 

[macelek01]

Hy Everybody!

I would like to ask some help in measuring. I have a faulty mbp logic board. It is a 820-2915-b (15”, 2011 early, 2.0Ghz).
The board turns on, but about 2 seconds turns off. If I press the power bottom the sleep led flashing one, the fans spin up, and after the board turns off.

I tried the smc reset, and start without smc, but the situation same as previously.

Can somebody give me idea how I can look for the issue? What should be measured?

Thanks a lot.

Today I measured the board. The clock generators work fine. I checked the power supplies. All of them works perfectly except CPU VCORE supplier. The CPU PWM regulator (MAX17511) get four controller signals from the CPU:

CPUIMVP_VR_ON =3,3V (I think it's good.)
CPU_VIDSOUT =1,05V (?)
CPU_VIDALERT_L =1,05V (?)
CPU_VIDSCLK =1,05V ( I checked with scope, but I didn't see normal clock signal.)

It seems to me the CPU didn't control it's own regulator. Now I have got any idea. Could you suggest to me anything to continue measuring?

 

[Monkeywrap]

Should stay solid at 12.5V. If it is dropping off then there is something in the charge circuit that is detecting a fault and "hiccuping".

With power off test the resistances of the surrounding circuitry. Particularly sense resistors. Also, measure the resistance between each pin and ground of the ISL6259 charger. The typical measurements can be found somewhere in the thread.

Started measuring from Magsafe connector and found out that Q7085 has interesting fluctuating voltages. Before Q7085 is Q7080 that has steady voltages 16.50V on PINS 5-8, 16.05V on PINS 1-3 and 15.85V on PIN 4 but Q7085 has 16.05V on PINS 1-3 and then PIN 4 fluctuating between 4V to 15.30V and PINS 5-8 fluctuating between 4V to 16.00V.

Does this mean that Q7085 is bad? Can you or someone measure voltages from known good board? I believe these are marked Q7000 and Q7001 on 13" MBP.

 

[bladerex]

Started measuring from Magsafe connector and found out that Q7085 has interesting fluctuating voltages. Before Q7085 is Q7080 that has steady voltages 16.50V on PINS 5-8, 16.05V on PINS 1-3 and 15.85V on PIN 4 but Q7085 has 16.05V on PINS 1-3 and then PIN 4 fluctuating between 4V to 15.30V and PINS 5-8 fluctuating between 4V to 16.00V.

Does this mean that Q7085 is bad? Can you or someone measure voltages from known good board? I believe these are marked Q7000 and Q7001 on 13" MBP.

I think you mean Q7030 and Q7035 on 13" i5 and i7
I don't have the schematics and .brd for that particular model but of what you are saying you have to check the connection between pin16 of U7000 and pin4 on Q7055 for short than check the current control U7000 CHGR_CSI_P pin28 to R7020 pin1 = 10 ohm , U7000 CHGR_CSI_N pin27 to R7020 pin2 = 10ohm.
on 13" MBP. Very often happens to be burned via on those connections.
Also check them for short to ground especially pin16 on U7000 (CHGR_BGATE), C7026 go bad sometimes.
But most of the time lead to burnout U7000. I cant help further without schematics and board view for your specific model.
But in any case I wish you luck.

 

[bladerex]

Here is some voltages around charger chip. Magsafe on and battery connected.

edit. and for additional info for everybody who wants to help: mid2010 mbp, doesn't charge, detects battery and tells cycles etc. works alone with battery, works with battery and magsafe, doesn't work with magsafe only (except smc bypass mode)

Before trying anything you can consider putting back R7002 (it is missing on your picture)
On some boards (820-2879-B) it is missing from factory also try measuring from U7000 both paths to R7020 and both paths to R7050 thru R7051, R7052 and R7021 R7022. It is definitely something around U7000.

 

[Monkeywrap]

I think you mean Q7030 and Q7035 on 13" i5 and i7
I don't have the schematics and .brd for that particular model but of what you are saying you have to check the connection between pin16 of U7000 and pin4 on Q7055 for short than check the current control U7000 CHGR_CSI_P pin28 to R7020 pin1 = 10 ohm , U7000 CHGR_CSI_N pin27 to R7020 pin2 = 10ohm.
on 13" MBP. Very often happens to be burned via on those connections.
Also check them for short to ground especially pin16 on U7000 (CHGR_BGATE), C7026 go bad sometimes.
But most of the time lead to burnout U7000. I cant help further without schematics and board view for your specific model.
But in any case I wish you luck.

No, I mean on 15" Q7080 and Q7085 are the same as Q7000 and Q7001 on 13" and MBP15 Q7030 is Q7020 on MBP13, MBP15 Q7035 is Q7021 on MBP13. At least in the shematics that I have, pics attached.

But measured short between pin16 U7000 and pin4 Q7055 and pin16 U7000 not short on ground.

 

[bladerex]

No, I mean on 15" Q7080 and Q7085 are the same as Q7000 and Q7001 on 13" and MBP15 Q7030 is Q7020 on MBP13, MBP15 Q7035 is Q7021 on MBP13. At least in the shematics that I have, pics attached.

But measured short between pin16 U7000 and pin4 Q7055 and pin16 U7000 not short on ground.

Do you have a solid connection between pin2 on R7020 and pin2 on R7021
also pin1 on R7020 and the other 10ohm resistor that i can't see... check the values of those two also.
I think U7000 shut down power supply because it thinks that machine consumes to much current.

 

[Monkeywrap]

Do you have a solid connection between pin2 on R7020 and pin2 on R7021
also pin1 on R7020 and the other 10ohm resistor that i can't see... check the values of those two also.
I think U7000 shut down power supply because it thinks that machine consumes to much current.

Solid connection between pin2 R7020 and pin2 R7021
Solid connection between pin1 R7020 and pin1 R7022
R7021 measures 10.5ohm and R7022 10.3ohm
U7000 CHGR_CSI_P pin28 to R7020 pin1 10.6ohm
U7000 CHGR_CSI_N pin27 to R7020 pin2 10.5ohm

 

[Nicohend]

A1369 (820-3023) does not charge

Dear all,

I think that all the information in this thread is extremely usefull, however i now have a macbook that i cannot fix. I was wondering if you guys maybe could help me.

I have a A1369 (mid 2011) MBA, which experienced liquid damage. I by the way have the board view and schematic of the MLB, not of the LIO. I replaced the J4700 header and the U9410 chip, since those were really corroded. The macbook runs smoothely again now, however it does not want to charge its battery, nor will it run from AC. It just depletes its battery and then dies. I have to recharge the battery in another MBA to get it running again.

So i started measuring, and the first problem I noticed is that the charger won't enable full voltage. It just remains at 6-7V. From testing with another MBA, i discovered that just a LIO-board connected to the MLB using the 6-pin connector (so with a disconnected flatcable) is enough to let the charger enable its full voltage. From this i deduce no communication with the SMC is needed. However, now i have no clue where to look for the problem. Does one of you guys know what triggers the magsafe charger to unleash its full voltage?
/e I found that it is just a small load between the power pins, and tested this using a 220kOhm resistor. This seems to be the case, since when attached, the magsafe unleases its full voltage. So apparently, with a battery connected the macbook isn't a large enough load and when no battery is connected, it is, however it shuts down immediately...
/e2 Actually i just saw that with a battery connected, the voltage also increases to 14V and then falls back to 6-7V and remains the same. Note that this also happens when the flatcable is disconnected...

Another observation I made is that when I connect the charger with no battery attached, the charger starts enabling its high voltage (climbing to 12-14V) and then it shuts it off again (0V), a second later it tries again, ans shuts off again, together with this the magsafe is blinking green. As if it is trying to power the board, and then something tells it to shutdown again. Does this mean there is some kind of short somewhere, and in that case, why isn't it doing that when a battery is attached?


Thanks in advance!

 

[eki84]

Macbook Pro A1278 - mid 2012 MD101

Hi everybody,

i have a big problem with the macbook from my sister. It has a liquid damage. First, does not turn on and no battery charging. Now ive replaced the ISL6259 and at least the battery is charging. But still does not turn on. Ive replaced the TPS 51125 with a new one but still no boot. When it is quiet, you can hear a "click" comes from the fan and a minimal movement of it. But no other reaction. I hope you guys have an idea... Thanks and regards from germany.

 

[saronno]

I am working on a A1342 logic board I found on a macbook bought
on ebay.

If you connect the magsafe you have the green light.
If you connect a battery the board charges it, no problem.
There is no evidence of liquid damage both in the case and
on the board.
If you try to jump the board no fan, no chime, no video, but cpu/gpu
get warm.
If you bypass the SMC fan starts at maximum speed, but no chime
and no video.

I am not sure it a gpu issue ... usually when the gpu is the problem
you still have chime and fan starts.

Checking the white fuse I find nothing. G3Hot is good. Board seems
to be powered correctly all over the place.

My guess is that since the fan starts bypassing the SMC,
in normal mode the SMC finds something it doesn't like.

Any idea?

Did you checked the 3V 5V lines? TPS511125 or something like that.

i have similar board and exact same results...



someone already posted it. just rename .zip to .brd

magsafe just connected
VO1 0
VO2 3,27

after jumping the board ...

VO1 4,95
VO2 3,27

It seems ok, right?

seems fine
Check the Pgood power guard i suspect somethings triggering the power guard ensuring it doesn't start. Previously i encountered a problem with MCP VCore rail that triggered the power guard meaning the smc was unhappy and wouldn't allow anything to proceed or the cpu to turn on.

pgood is 0v

... always before and after jumping the board ...

Okay.
So jump the power debugging switch pads (r5015 usually)
Measure all the inductors on the underside of the board for voltages for s0 rails
start with

CPUVCCIOS0 (l7630 inductor
PVCCSA (l7100 inductor)
and report back.

Do you have the brd of the board?
I found the brd of the 2010 model but it's a bit different ...

However I think they are named differently on my board ...

Image

after jumping
CPUVTTS0_PGOOD 0,75 (but I get also 0 the second and the third time I check)
P5V3V3_PGOOD should be the PGOOD pin of 51125 and it's 0.
MCPCORES0_PGOOD is generated by isl6263 .... but I can't check it
because I don't' find a pad (it goes directly on the bottom thorugh the
board).

the inductors i asked you to check where ofcourse from a different board. Doh.

check if those chips are outputting voltage. Do this by going to there U refrence number and finding the inductors there to smooth the final voltage output.
Check all the rails in the picture for voltage, if one is not right then that will be the first chip to investigate as it is most likely to be the cause of this.
Thanks

I have to admit that I gave up for a while ... today I have found the will
to troubleshooting this board.

Looking aroud the schematics I found that all the lines converging to pgood
are open drain ... so I wonder how to understand which chip signals that
there is something wrong: the resistors connecting toghether the signals
are very low so it's almost impossibile to measure a voltage between the
pin of the single resistor to understand if the current is flowing in it.
I can of course desolder one after another the pull-up resistor ... anything else?

Anyway, I bypass the smc: fan runs cpu get voltage and get warm
but system doesn't do anything ... no chime, no video, no white led blinking ... so I think cpu doesn't really do anything or bios it's dead.
But if you bypass the smc magsafe led it's not full green anymore so I think
it's something hardware and not the bios.

 

[saronno]

Ok ... I found out that PPVCORE_S0_CPU is 0 (after smc bypass) ... it
should have been 1,25V.
PP1V05_S0_CPU is 1,05 so it's ok.

PPVCORE_S0_CPU is generated by ISL9504 ...

 

[alz0rz]

Hello all, what a great thread this is, I've been scavenging from it trying to figure out my problem with no luck. Here is my situation.

Early 2011 MBP. MB: 820-2915-B

The Magsafe light is dim green and that is all, no power, nothing.

I am getting good voltages from DC-in board. So after some reading I jumped to checking U7000.

U7000 Pin 3 reads 0V which is the reading I'm getting from R7011.
R7010 I am getting 16.5V on one side and 0V on the other. I read I'm supposed to be getting about 4V out of here?

Does anyone have any suggestions? Thanks!!

 

[saronno]

I am working also on a 1278 MBP board ... and this one have problem
to charge the battery and working with both magsafe and battery together.
It works on battery, it works on magsafe but it freezes if I attach both.

But very strage thing is that if I put a bit of Isopropilic alcohol on
u7000 (alias isl6259) it works for a couple of minutes and charges
the battery. When the alcohol dries it fall back to the previous status.

Can someone explain me why?