SMC Issue on MBP 13 - Hardware Troubleshooting Guide

[SKRMobiletech]

Does your Magsafe light up? Go to page 60 of the schematic and check the G3hot main supply, check voltage on these Q6910, Q6915, U6915, U6990..Also check D6905 see if you get 16V to pin1, if not hook up the working battery and check pin3 if you get 12V there. put your multimeter to continuity and check there ICs to find if anything is shorted to ground, when it beeps on the non-ground pin, then you'll know it's shorted, lookup schematic and check which line the short is at, short can happen on multiple lines depending on how severe it got liquid damaged

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Thanks T0p0ne for your input I will try probing again this week end I will concentrate on the page 60 that you mention. I and will post the result later. Yes Magsafe light up solid Green.

T0p0ne: The schematic diagram I have it doesn't show me where those location of the Q6910,Q6915,U6990 and D6905. Could you please tell me where I can find them on the board. Thanks I do really appreciate your time.

 

[t0p0ne]

Does your Magsafe light up? Go to page 60 of the schematic and check the G3hot main supply, check voltage on these Q6910, Q6915, U6915, U6990..Also check D6905 see if you get 16V to pin1, if not hook up the working battery and check pin3 if you get 12V there. put your multimeter to continuity and check there ICs to find if anything is shorted to ground, when it beeps on the non-ground pin, then you'll know it's shorted, lookup schematic and check which line the short is at, short can happen on multiple lines depending on how severe it got liquid damaged

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Thanks T0p0ne for your input I will try probing again this week end I will concentrate on the page 60 that you mention. I and will post the result later. Yes Magsafe light up solid Green.

T0p0ne: The schematic diagram I have it doesn't show me where those location of the Q6910,Q6915,U6990 and D6905. Could you please tell me where I can find them on the board. Thanks I do really appreciate your time.

If we're talking about MBP 15 2008 80-2330, see the attachment for page 60

 

[t0p0ne]

I have tried with other fan but the problem continues.

I have 3.42v on G3HOT. When i put the charger the magsafe put on green light and if i connect the battery he turns the orange light but when i turn the mbp on no fan spining and no chime.

What can i check to give you more details?

The F9800 or R5095 can interfer with this problem?

Thanks

How do you turn it on, by shorting the pads or keyboard, how do you know the keyboard is good, especially after the spill? The fact that you get green and orange light is the good sign that Charger IC may be ok, and the issue you can't start the board may lie between SMC U4900 and U7201 ICs, check these two lines: SMC_PM_G2_EN from SMC & P3V3S5_EN_L to U7201
It's best if you have microscope to look at these ICs see if any pin or pad is corroded and broken

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on this third board, it start, fan spin, all seems ok, but no chime and no post.

A post from laptech may shed some insight your third board: https://forums.macrumors.com/posts/17858228/

Try to remove heatsink and use your finger to sense the heat from CPU & GPU see if they heat up, if not then they may not getting required power to start_> hence there is the culprit

 

[SKRMobiletech]

If we're talking about MBP 15 2008 80-2330, see the attachment for page 60

Top0ne :


Can you please show where this location on the actual logic board? Thanks

 

[dellxps15]

if i have all voltages on almosto all coils except in one, isnt more easy to just check this coil number and see the schematics? i havent a .brd for that mainboard, so it's hard to spot the right number.

edit: that mainboard need more investigation, as for now looks like it got all voltage.

edit2: i replaced the backlight fuse and now it's burned again , does a 820-2567 use lcd ccfl or led panel?

can be that make the fuse blow as far i have led panel only here;

How do you turn it on, by shorting the pads or keyboard, how do you know the keyboard is good, especially after the spill? The fact that you get green and orange light is the good sign that Charger IC may be ok, and the issue you can't start the board may lie between SMC U4900 and U7201 ICs, check these two lines: SMC_PM_G2_EN from SMC & P3V3S5_EN_L to U7201
It's best if you have microscope to look at these ICs see if any pin or pad is corroded and broken

----------



A post from laptech may shed some insight your third board: https://forums.macrumors.com/posts/17858228/

Try to remove heatsink and use your finger to sense the heat from CPU & GPU see if they heat up, if not then they may not getting required power to start_> hence there is the culprit

 

[t0p0ne]

Top0ne :


Can you please show where this location on the actual logic board? Thanks

I wish i could help but they are in different locations on the board,both top & bottom side, that's why you need schematic and boardview file to help you pinpoint them

 

[t0p0ne]

if i have all voltages on almosto all coils except in one, isnt more easy to just check this coil number and see the schematics? i havent a .brd for that mainboard, so it's hard to spot the right number.

edit: that mainboard need more investigation, as for now looks like it got all voltage.

edit2: i replaced the backlight fuse and now it's burned again , does a 820-2567 use lcd ccfl or led panel?

can be that make the fuse blow as far i have led panel only here;

MacBook Uni A1342 2009 all uses LED screens, make sure the screen cable and LVDS connector are good and not corroded. Also you replaced the fuse with same value? Does it burn if you power on without the screen attached?Your BKLT voltage is fed by line PPBUS_G3H, what's your read on the F7000?
Btw, the coil you questioned earlier looks like it's L7560, i'd try to give you a reading on this when i have a chance to check my board

 

[dellxps15]

MacBook Uni A1342 2009 all uses LED screens, make sure the screen cable and LVDS connector are good and not corroded. Also you replaced the fuse with same value? Does it burn if you power on without the screen attached?Your BKLT voltage is fed by line PPBUS_G3H, what's your read on the F7000?
Btw, the coil you questioned earlier looks like it's L7560, i'd try to give you a reading on this when i have a chance to check my board

sorry, this one is the no voltage coil and also the upper component has no voltage....

is this the backlight coil ?

 

[t0p0ne]

sorry, this one is the no voltage coil and also the upper component has no voltage....

is this the backlight coil ?

The big coil is L9710 and the smaller is C9715, both part of BKLT components
L9710 gets power from R9700 thru line PPVIN_BKL to pin#1 of BKLT driver, you need to trace back this line if you don't have power to L9710 at pad1
Here's brd for A1342 but for 2010, which is similar to 2009 except for layout is flipped compared to 2009,but ICs position is close, change .zip to .brd

 

[dellxps15]

The big coil is L9710 and the smaller is C9715, both part of BKLT components
L9710 gets power from R9700 thru line PPVIN_BKL to pin#1 of BKLT driver, you need to trace back this line if you don't have power to L9710 at pad1
Here's brd for A1342 but for 2010, which is similar to 2009 except for layout is flipped compared to 2009,but ICs position is close, change .zip to .brd

thank you very much. ill check this later

edit: changed again the backlight fuse. and have 13.5 volt both side with magsafe connected.

L9710 get 0.9volt when plugged magsafe for the first time, then voltage decrease to 0 after some time. now plug in and off magsafe, coil 9710 remain to 0, but fuse has 13.5volt both side. would like to power sistem on, but keyboard seems to get broken fter many macbook try out

resistor R9700 if i put multimeter to 200ohm, oscillate from 6 to 10.

 

[cmdrdata]

SMD work?

I am helping to revive a friend's mid2009 MBP13 (K24, logicboard 820-2530A) that suffered small liquid damage. As far as I can tell the area around G3HOT has a problem. R6905 (47 Ohms) was missing, and possibly D6905 is also damaged (pin5 looked corroded). I get no G3HOT with either magsafe or charged battery. Voltage divider R6995/R6996 are also suspect. I get 125K/113K Ohms respectively, but this could be because of other components in the system. When I connect the magsafe (after the board is powered off overnight, I get a brief flash of green (less than a second) on the magsafe plug and then nothing else. DCIN goes up to 16-17v then goes away ( I think this is normal if there is no system load power draw from the magsafe and G3HOT failed to come on. If the board is not allowed to discharge overnite, the brief flash does not occur.
My problem is I am too old (almost 68) to be able to work with these tiny components. Although I do have a stereo microscope, fine point solder iron, my eyesight and hand work is just not good enough to attempt to fix it. What do you all suggest?

 

[triplelucky]

cmdrdata,

Can you tweak your working techniques to help you overcome those physical limitations?

What is giving you the most trouble?

Usually there is some way to overcome obstacles.

 

[chigwelldave]

I am helping to revive a friend's mid2009 MBP13 (K24, logicboard 820-2530A) that suffered small liquid damage. As far as I can tell the area around G3HOT has a problem. R6905 (47 Ohms) was missing, and possibly D6905 is also damaged (pin5 looked corroded). I get no G3HOT with either magsafe or charged battery. Voltage divider R6995/R6996 are also suspect. I get 125K/113K Ohms respectively, but this could be because of other components in the system. When I connect the magsafe (after the board is powered off overnight, I get a brief flash of green (less than a second) on the magsafe plug and then nothing else. DCIN goes up to 16-17v then goes away ( I think this is normal if there is no system load power draw from the magsafe and G3HOT failed to come on. If the board is not allowed to discharge overnite, the brief flash does not occur.
My problem is I am too old (almost 68) to be able to work with these tiny components. Although I do have a stereo microscope, fine point solder iron, my eyesight and hand work is just not good enough to attempt to fix it. What do you all suggest?

Hi Cmdrdata,

A trick I've used a couple of times with G3Hot problems is to use an external bench PSU to test the rest of the board. You can solder a couple of wires onto ground and L6995 and supply an external 3.4v with the current limit on the PSU set at 250mA. Then, if the board boots correctly, you will know if it's worth fixing the on-board G3Hot. I agree it is very hard to do manual rework but using a hot-air soldering station or Pyropen and tweezers it's not as bad as a standard iron.

Best regards,

Chigwelldave.

 

[South657]

Hi Cmdrdata,
I am working on 2011 board with no G3 hot, all looks good until I get to U6990 no volts to L6995 I was thinking of doing the same trick as Chigwelldave, as the fault is open and not a short he has confirmed it works so I will now do that, and let you know how I get on. My eyes are not too good and I shake like Louis Rossmann, and changing U6990 is hard for me so I will get a friend with good eyes and good rework skills to do that, but only if I have a positive result from that trick. Finding the fault and getting chime is the biggest buzz for me.

Regards
South 657

 

[triplelucky]

Here is what I use to do “precision nudging” to “float in” a QFN so that it “snaps back” into perfect position after the solder becomes liquid.

I can use both hands and rest them on the bench, to steady and control the tweezers or other poking instrument, which gives me a great deal of precision.

The arm is repurposed from a security cam base with a microphone holder attached to one end. The hot air gun fits in there nicely.

I position the logic board, put the hot air gun in the holder and position it with the arm and turn it on.

When I’m ready to go I swing in a bench magnifier that has two 10X lenses together in series that allows me to see well enough to do the job.

I am 62, can’t see that well and have arthritis in my hands.

This setup allows me to easily replace a QFN that looks “factory”.

 

[nicoar10]

A1278 2.4 2010 820-2879 no post or chime

Hi guys!

I got a a1278 boards, with some liquid spilled and now clean totally.

I measured some volt

i got:

3.42v G3HOT
TPS51125 3v and 5v present
Charger circuit works perfectly and show green / orange light on magsafe.

Now the issue is no post or chime. No fans working when press power pads or power button from keyboard.

Im lost on this board. Where i need to measure to follow the power circuit?

Regards!

Attach schematic and boardview

https://www.dropbox.com/sh/g7y3vz361xvvl0n/RrDsOIiZzX

 

[eki84]

Hi guys,

good Job here. Ive been following this Forum for a Long time. Now i have a problem. My Mac A1278 Mid 2010 does not turn on with Magsafe AC Adapter. When i connect the magsafe, the green LED turns on, but it does not Charge the battery. So the green light does not switch to orange. When i connect a full charged battery, it turns on normaly. So it turns on with Battery.

What ive already done:

- Changed the 6259AHRTZ chip
- Changed the DC-In Board
- Changed the Magsafe
- Changed the Battery
- Start with the minimum settings (no Keyboard, no Camera, no Touchpad..)


same Problem. I dont know what the problem is. The Board is clean. No liquid to see. Any ideas? Please help. Thanks in advance.

Regards from Germany

 

[cmdrdata]

Hi guys,

good Job here. Ive been following this Forum for a Long time. Now i have a problem. My Mac A1278 Mid 2010 does not turn on with Magsafe AC Adapter. When i connect the magsafe, the green LED turns on, but it does not Charge the battery. So the green light does not switch to orange. When i connect a full charged battery, it turns on normaly. So it turns on with Battery.

What ive already done:

- Changed the 6259AHRTZ chip
- Changed the DC-In Board
- Changed the Magsafe
- Changed the Battery
- Start with the minimum settings (no Keyboard, no Camera, no Touchpad..)


same Problem. I dont know what the problem is. The Board is clean. No liquid to see. Any ideas? Please help. Thanks in advance.

Regards from Germany

1. Green LED is a good thing, and I'd guess that G3HOT is ok.
2. On magsafe alone if you don't have 12v on the fuse by the battery, then look for the 2 power FETs that are driven by the 6259. The top should have DCIN voltage (~16v) and the gates of these two FETs should be no more than 12v. They should be pulses driven of opposite polarity driven by 6259 chip.

 

[eki84]

1. Green LED is a good thing, and I'd guess that G3HOT is ok.
2. On magsafe alone if you don't have 12v on the fuse by the battery, then look for the 2 power FETs that are driven by the 6259. The top should have DCIN voltage (~16v) and the gates of these two FETs should be no more than 12v. They should be pulses driven of opposite polarity driven by 6259 chip.

Thank you for your reply. But where are this FETs?

Thanks

 

[t0p0ne]

Thank you for your reply. But where are this FETs?

Thanks

Boardview and schematic are your friends, check this post to find them if you don't have them. Then check to see if 16V arrives at Q7030 and 12V at Q7035, then check Q7055 for 12V if Q7030 & Q7035 check out ok, otherwise back track if either of those FETs not getting the desired voltage

 

[chigwelldave]

Hi nicoar10,

You seem to have your main supplies so check page 65 - Power Sequencing. Check the other S0 Rail Enables are active and the ALL_SYS_PWRGOOD. It won't boot until this signal is up.

Regards,

Chigwelldave.

 

[RiverMan420]

U7000

Does anyone here have a diagram of U7000 for an 820-2879 board showing which pins are inputs and which are outputs? Seems like I have a lot of trouble with this IC. It would sure help a lot if I knew how to test this chip. I see 5v on 19 and 20 most of the time but other voltages are off a lot of times and I never know if it's U7000 not providing the proper voltage or something else

 

[eki84]

Boardview and schematic are your friends, check this post to find them if you don't have them. Then check to see if 16V arrives at Q7030 and 12V at Q7035, then check Q7055 for 12V if Q7030 & Q7035 check out ok, otherwise back track if either of those FETs not getting the desired voltage

So ive measured Q7030, Q7035 and Q7055. The result is:

Q7030: ~6,5V - 7,2V
Q7035: ~1,0V - 1,2V
Q7055: ~1,0V - 1,2V

it seems that the problem is here. No correct voltage on the MOSFETs..What could be the reason?

EDIT: When i connect the batterie, i have 11V on Q7030 and 11,5V on Q7035 and Q7055.

2. EDIT: Now the green light is completely off. I was measured the 6259AHRTZ and checkt the voltages. Then the green light turns off. But i still have 6,5V on Q7030 and 1V on Q7035 and Q7055...

 

[dellxps15]

big problem for me arent qfn annymore. now i use a 4x magnifier very small but with the good flux quality it get in position almost by itself. big problem are 0402 that fly anywhere and ull discover them later on the table

really hate that....

Here is what I use to do “precision nudging” to “float in” a QFN so that it “snaps back” into perfect position after the solder becomes liquid.

I can use both hands and rest them on the bench, to steady and control the tweezers or other poking instrument, which gives me a great deal of precision.

The arm is repurposed from a security cam base with a microphone holder attached to one end. The hot air gun fits in there nicely.

I position the logic board, put the hot air gun in the holder and position it with the arm and turn it on.

When I’m ready to go I swing in a bench magnifier that has two 10X lenses together in series that allows me to see well enough to do the job.

I am 62, can’t see that well and have arthritis in my hands.

This setup allows me to easily replace a QFN that looks “factory”.

 

[t0p0ne]

Does anyone here have a diagram of U7000 for an 820-2879 board showing which pins are inputs and which are outputs? Seems like I have a lot of trouble with this IC. It would sure help a lot if I knew how to test this chip. I see 5v on 19 and 20 most of the time but other voltages are off a lot of times and I never know if it's U7000 not providing the proper voltage or something else

Here's the U7000 voltage when Magsafe is plugged in, i took the measure from my MBP 13 2012, you should have similar voltage for U7000 to function correctly

So ive measured Q7030, Q7035 and Q7055. The result is:

Q7030: ~6,5V - 7,2V
Q7035: ~1,0V - 1,2V
Q7055: ~1,0V - 1,2V

it seems that the problem is here. No correct voltage on the MOSFETs..What could be the reason?

EDIT: When i connect the batterie, i have 11V on Q7030 and 11,5V on Q7035 and Q7055.

2. EDIT: Now the green light is completely off. I was measured the 6259AHRTZ and checkt the voltages. Then the green light turns off. But i still have 6,5V on Q7030 and 1V on Q7035 and Q7055...

Clearly you have power issue getting to Q7030 & Q7035 which comes from U7000 and/or related area, now green light is out when you were probling around U7000 suggests problem may be there, U7000 now may be shorted, put your multimeter to continuity and check pins around U7000 to find if any one shorted to ground then you'll know, if it appears on then use my U7000 voltage sample to check against yours, i'm sure you'd find something interesting