820-3787

[pws6074]

I have a board with no water damage or something close to that.
The board don't have green light, however, i get 3.42V and 17V
I check R5187 (SMC ACOK) Pin 2, I get 3.42V and SMC_ONOFF_L as well.

U7000
Pin 1 = 0
Pin 5 = 0

C7008 = 3.42V

CHGR_CSI_P Pin 28 = 3.9Ω short to ground (something is not right here)
I don't have PPBUS_G3H.

I feel a little lost. Can you guy help me out?

Thank you

 

[larossmann]

If you have a 3.9 ohm short to ground on pin 28 of U7100 then you likely have a bad U7100 or bad C7121. I would start by replacing this. I am surprised that you have SMC_BC_ACOK though if this is the case.

1) Does U7000 have 3.42v on pin 1?
2) Is R7029 on the board?
3) Is SMC_RESET_L present?

If all that is good I would start replacing U7100.

 

[dukefawks]

There is a short on PPDCIN somewhere. I doubt it will come from U7100. See if short is also present on R7120 and inject voltage there, see what heats up.

 

[pws6074]

1) Does U7000 have 3.42v on pin 1? Yes,
2) Is R7029 on the board? Yes,
3) Is SMC_RESET_L present? Yes,

I replaced the U7100 and i get my PPBUS_G3H, however, my green light still off plus, my 5V is 4V.

Do you think i need replace again the U7100?

Thank you for sharing your knowledge, Louis & Duke.

 

[dukefawks]

Exact voltage on PPBUS? ACOK present?

 

[pws6074]

PPBUS = 12.36V
ACOK = 3.44V from R5187 PIN 1


L7095 = 3.4V

 

[dukefawks]

12.36 means SMC is not running. SMC_RESET high? If yes then probably dead SMC or crap under it.

 

[pws6074]

R7100 smc_reset pin 1 = 3.4v
PP5 = 0.04V

 

[JohnB8812]

So then crap under or SMC or dead SMC. Try running flux under it first. Make sure you remove edge bonding, but 12.36 is high enough for hope it's not dead lol.

 

[pws6074]

I did, plus i put the board in the super sonic machine.

 

[dukefawks]

Time to put another SMC on there.

 

[pws6074]

SMC Replaced and everything looks normal, however, the audio doesn't work.
If i plug the Headphone nothing change as well.
Any hint from here?

Thank you guys

 

[dukefawks]

Any audio device recognized? Can adjust volume in OSX?

 

[pws6074]

Yes, i can.
When i plug the headphone, they system recognize as well, however, no sound

 

[dukefawks]

Inspect U6201 area and voltages to it. No chime also?

 

[pws6074]

Yes, no chime sound.

 

[pws6074]

U6201 Pin1 / C6212 - 3.4V
C6215-17 = 4.5V

 

[dukefawks]

Not that much that could be wrong. I assume you did a PRAM reset and there still is no chime? It does look like a dead U6201 then.

 

[pws6074]

I will replace and let you know.
Thank you