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SMC Issue on MBP 13 - Hardware Troubleshooting Guide
- Thread starter Dadioh
- Start date
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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?
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?
my entire repair work has turned to mush
The baords i was talking about have made no progress
Another board came in for a u7000 replacement, replaced the chip and got all the same problems as my other baord. I think its due to oxidised and old chips that become very difficult to solder with. This issue has only recently occurred and ive done quite a few of these repairs before, i think its a certain supplier thats caused this.
A board i desperately need sorted is now quite nearly there i hope.
I have 12v, g3hot, 3.2v on pin 14 of u7000, everything seems to be firing as normal.
However everytime i put a load on it (put the fuse back in place) the fets q7030 and q7035 blow up.
I think its because for some reason q7080 and q7085 are only givving it 11v and fluctuating therefore running the fets under there standard operating voltage causing them to blow
I cant figure out why, both the inrush fets are fine, so are the gate resistors.ect
Hi ZZZAC,
Yes i think you have a point on bad chips, I have heard that old ones are re sold and are not tested as any good from old rejected boards
the ones with whole in. As you know i have a board with bad fets Q7030 7035 i will change them first and let you know how i get on.
Still trying to get K87 board view file can any one help please.
Regards
South657
I actualy narrowed it down to the Q7080 and Q7085 fets i was using. The 'new ones' i had in stock were the route cuase of four full days of missery.
My ISL chips wernt grate either but seemed to work on a on off sort of hit and miss basis.
Q7030 and Q7035 can fail to. just ensure you get 16v to it and insure you are getting the correct voltage to the gate of the fet.
Usualy measure no resistance or get really hot when they fail
As for a K87 board view youll have to buy one, ive got allot of files and would help if i had it but i dont.
http://www.laptop-schematics.com/ have it...
Would be awesome if you could share here if you buy it.
So glad i got atleast one of my few boards working!
good luck with yours
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.
RAM Issue:: One Beep in each slot / Power on itself - A1278 2010 2.4
Another logic board arrive, i think was water spilled.
Dead board, no g3hot , no 5v 3v.
After replace charger circuit get 3.42, charge battery good and 5v and 3v present.
Now when connect magsafe or battery power on itself but no post or chime.
Just beep one time like a no ram installed status.
Board is in excellent conditions and ram slot are so good.
Now take some measures in TPS51116 ( 1.25 / 1.5) and all volt are correct.
Any simillar issue resolved??
Thanks.
Another logic board arrive, i think was water spilled.
Dead board, no g3hot , no 5v 3v.
After replace charger circuit get 3.42, charge battery good and 5v and 3v present.
Now when connect magsafe or battery power on itself but no post or chime.
Just beep one time like a no ram installed status.
Board is in excellent conditions and ram slot are so good.
Now take some measures in TPS51116 ( 1.25 / 1.5) and all volt are correct.
Any simillar issue resolved??
Thanks.
pgood is 0v
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 ...
on my macbook core duo, after changing u7000 and a k0305 component, now magsafe without battery is green and on battey fuse i have 16 volt.
without magsafe and only battery, battery indicator is ok.
now problem is:
if i have magsafe connected and put also battery, magsafe pass from stable green to a slow blinking green. where i have to look at ?
macbook now power on both magsafe only and battery only, but no chime no post.
but first i have to focus on that slow blinking magsafe.
edit: already had that blinking magsafe. pur a new u7000 thinking i did solder it bad (yes soldered many qfn now and im a bit ok at them), but problem is still the same
Edit2: with magsafe only, if i look at battery fuse. i have stable 16 volt, but if i look on battery pin connector, i have stable 3.5volt at pin 4 and 6. 0 volt to pin 5-7-8-9. problem are pin 1-2-3 with oscillating 16 volt. i have here 16 volt and about every 5 seconds it goes to 0.4 volt (or 0 volt) and then again up to 16 volt.
dunno if i put pin number in wrong order.
on the board 820-2567, fan start at max and almost all component get warm (ram cpu ich, gfx) no post no chime ofcourse. only fan at max speed and component getting very hot. misuserd some coild and i have:
3v, 5v, 1v, (1.4volt down the ram), (0.9 volt near gfx-ich), (0.85volt between gfx and cpu the smallest one) (1.2volt, 1.2volt near cpu)
without magsafe and only battery, battery indicator is ok.
now problem is:
if i have magsafe connected and put also battery, magsafe pass from stable green to a slow blinking green. where i have to look at ?
macbook now power on both magsafe only and battery only, but no chime no post.
but first i have to focus on that slow blinking magsafe.
edit: already had that blinking magsafe. pur a new u7000 thinking i did solder it bad (yes soldered many qfn now and im a bit ok at them), but problem is still the same
Edit2: with magsafe only, if i look at battery fuse. i have stable 16 volt, but if i look on battery pin connector, i have stable 3.5volt at pin 4 and 6. 0 volt to pin 5-7-8-9. problem are pin 1-2-3 with oscillating 16 volt. i have here 16 volt and about every 5 seconds it goes to 0.4 volt (or 0 volt) and then again up to 16 volt.
dunno if i put pin number in wrong order.
on the board 820-2567, fan start at max and almost all component get warm (ram cpu ich, gfx) no post no chime ofcourse. only fan at max speed and component getting very hot. misuserd some coild and i have:
3v, 5v, 1v, (1.4volt down the ram), (0.9 volt near gfx-ich), (0.85volt between gfx and cpu the smallest one) (1.2volt, 1.2volt near cpu)
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Boardview 820-3115b
hello,does anyone have the j30 brd?
i have brd for 820-2879, 820-3209 , 820-2530 k24 and brd for MacBook late 2008 early 2009.
hello,does anyone have the j30 brd?
i have brd for 820-2879, 820-3209 , 820-2530 k24 and brd for MacBook late 2008 early 2009.
However I think they are named differently on my board ...
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).
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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
on my macbook core duo, after changing u7000 and a k0305 component, now magsafe without battery is green and on battey fuse i have 16 volt.
without magsafe and only battery, battery indicator is ok.
now problem is:
if i have magsafe connected and put also battery, magsafe pass from stable green to a slow blinking green. where i have to look at ?
macbook now power on both magsafe only and battery only, but no chime no post.
but first i have to focus on that slow blinking magsafe.
edit: already had that blinking magsafe. pur a new u7000 thinking i did solder it bad (yes soldered many qfn now and im a bit ok at them), but problem is still the same
Edit2: with magsafe only, if i look at battery fuse. i have stable 16 volt, but if i look on battery pin connector, i have stable 3.5volt at pin 4 and 6. 0 volt to pin 5-7-8-9. problem are pin 1-2-3 with oscillating 16 volt. i have here 16 volt and about every 5 seconds it goes to 0.4 volt (or 0 volt) and then again up to 16 volt.
dunno if i put pin number in wrong order.
on the board 820-2567, fan start at max and almost all component get warm (ram cpu ich, gfx) no post no chime ofcourse. only fan at max speed and component getting very hot. misuserd some coild and i have:
3v, 5v, 1v, (1.4volt down the ram), (0.9 volt near gfx-ich), (0.85volt between gfx and cpu the smallest one) (1.2volt, 1.2volt near cpu)
Im pretty sure you should get 12v rather than 16v?
maybe its an older board or something idk, but i would never chuck 16v through a system that runs on 12v. You may be pushing the mosfets that are fed by the main rail a little harder than normal and could damage some components.
I usually pull f7040 and ensure the charging circuit has the correct voltage before letting power flow to the rest of the system.
i just realised this comment wasnt really that helpfull.
Good luck
tnx for reply. schematic talk about a range of 9-16volt, so 16volt is ok.
edit: i have not stable voltage also on Q7055 pin 4 and 5 have 16volt, going to low voltage every 5 seconds.
Edit2:
yes, today i got another mainboard from a 13'' i7. as seller told me he got 2 problem:
first is ram slot holder have broken both from one side. second one bank of ram is not working.
now i have changed (home repair) but working great
the 2 ram slot holder, and now pc start with each of banks, but there are 2 strange things:1° when i jump the 2 hole for startup pc , pc start ok, but fan go a bit too much fast.
2° if i plug magsafe (i have only magsafe 1 here) pc start automatically.
edit for this i7: after plug hdd cable and something else, i was able to load into osx and fan spin normally
i did shut down and pc powered off normally. cant make osx change as i havent password on that hdd taken from another macbook pro i have bought.
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tnx for reply. schematic talk about a range of 9-16volt, so 16volt is ok.
edit: i have not stable voltage also on Q7055 pin 4 and 5 have 16volt, going to low voltage every 5 seconds.
Edit2:
yes, today i got another mainboard from a 13'' i7. as seller told me he got 2 problem:
first is ram slot holder have broken both from one side. second one bank of ram is not working.
now i have changed (home repair) but working great
1° when i jump the 2 hole for startup pc , pc start ok, but fan go a bit too much fast.
2° if i plug magsafe (i have only magsafe 1 here) pc start automatically.
edit for this i7: after plug hdd cable and something else, i was able to load into osx and fan spin normally
How did you replace ram slot? there are so many pins to solder.
In i5 and i7 processors when you plug magsafe power on automatically.
For fan spin at high speed is maybe you have trackpad unplugged.
Trackpad has internal sensor.
tnx you very much, infact after plugin trackpad and hard disk pc fan spin normal.
for the ram slot repair, ill upload a tutorial.
i paid that mainboad 95 euros just changed ram slot + solder back one capacimeter taken from a very bad i5 board (posted picture of that some posts before) that has many damaged track and many missing component.
tnx for reply. schematic talk about a range of 9-16volt, so 16volt is ok.
edit: i have not stable voltage also on Q7055 pin 4 and 5 have 16volt, going to low voltage every 5 seconds.
Edit2:
yes, today i got another mainboard from a 13'' i7. as seller told me he got 2 problem:
first is ram slot holder have broken both from one side. second one bank of ram is not working.
now i have changed (home repair) but working great
1° when i jump the 2 hole for startup pc , pc start ok, but fan go a bit too much fast.
2° if i plug magsafe (i have only magsafe 1 here) pc start automatically.
edit for this i7: after plug hdd cable and something else, i was able to load into osx and fan spin normally
The problem, will probably be in the charging circuit
L7030 outputs 12v to the rest of the system... not 16v. ive only seen 16v on the output when there has been a problem in the charging circuit. Replace the U7000 chip. Im sure its not right untill theres 12v going to the system not 16v!
i agree...
You need to isolate circuit removing inductor.
Think that 12.5v is going out from charger circuit to supply tps51225 power supply ( 3v and 5v). If you have 16v probably your 3v5v power supply is bad or near to be.
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tnx for reply, but this is the 3rd u7000 i change in this laptop....
ill go for the forth hoping this time all will be ok...
ps: i've measured all u7000 pins:
here they are: with battery only and only with magsafe on the right
pin number:
1: 6.5v 0v
2: 0v 16.20
3: 0v 6v
4: 1.88v 5v
5: 0v 0.72v
6: 1.87v 3.38v
7: 0v 0v
8: 0v 0.03v
9: 0v 0.02v
10: 1.88v 3.88v
11: 1.88v 3.88v
12: 1.88v 3.88v
13: 0.12v 3.38v
14: 0v 0v
15: 0v 0.03v
16: 4.74v oscillate from 15v to 9volt
17: 11.71v 15.94v
18: 11.59v 15.82v
19: 0v 5v
20: 0v ? (too hard to read with my multimeter pencil too big )
21: 0v 0v
22: 0v 0v
23: 11.72v 15.94v
24: 11.71v 15.82v
25: 11.19v 13.98v
26: 9.6v 15.95v
27: 11.71v 15.96v
28: 11.71v 15.96v
is it true that i have to change another u7000?
PS: some tiems ago i had to change 2 capacimeters because lost them while working on u7000 desolder
: C7026 and C7002.edit: tooked a a1342 mainboard and with only magsafe on F7040 i have 12.5v as u say....
Edit2: i see on the schematic that on q7030 and on q7035 i have reported in schematic that they can carry 18v max so 16v on that pins should be rok ?
PS: yesterday, before change u7000, i see q7035 was shorted again (yes changed one some times ago), so changed it again and then changed u7000. today i spot a 0402 resistor (probably a fly one) touching c7000 and c7001 (both on ground side....)
on q7055 too i have only 16v.
are the 12.5 volt output from u7000 directly at a certain pin number, or u7000 vout 16v and then with some capacitors and resistor we get the 12.5 volt ?
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