A2289 820-01987-A water demage

[macfix_hh_25]

Hello everybody,
I have a MacBook Pro A2289 in the shop. It came in with light water demage, no power 5.209V - 5.213V / 0.014A. Corrotion was found around C7055 (PPBAT_G3H_CHRG_REG).
Disconnceting the battery solves the problem. MacBook starts normally and boots to login.

We cleanded the area and replaced C7055 and C7054, as they were badly corroded.
With connceted battery, its still the same. No power and voltage by 5.213V / 0.014A

C7051 = 12.62V (Pin1)
F7000= 12.62V (Pin 1+2)

Does that mean the battery is the problem or do we miss on something here?

Thank you for your feedback.
Tim

​

 

[2informaticos]

What is the exact 820-xxxx code of your board?
02020 is A2338 M1, not Intel A2289.

If you have 01987 board, check resistance (ohm scale) over C7020.

 

[macfix_hh_25]

Sorry, you're right. It's 01987 board. 02020 was the done board for C7055 and C7054

C7020 has 3.4 ohms

 

[2informaticos]

That looks good.
Just in case, check at C7023 too.

Be sure Q7065 isn't shorted D-S.
Check continuity for all traces in the area; solders also.

Also check diode mode to ground at SCL/SDA lines of battery bus; before and after Q6950.

 

[macfix_hh_25]

C7023 = 2.4 ohms
Q7065 isn't shorted D-S pins (222 - 775k Ohms) = OL in diode mode
diode mode to ground at SCL/SDA lines of battery bus; before and after Q6950 = OL

 

[2informaticos]

"Q6950 = OL"
ALWAYS check with red probe connected to ground!

HOW TO collection

I hope this "How to" collection will help our members. I will possibly modify this post in time, if updates available. Trigger SMC_ONOFF_L (PMU_ONOFF_L): It reffers to simulate power button function, when the keyboard is not connected. We need to do this when we work with the board...

boards.rossmanngroup.com

 

[macfix_hh_25]

Sorry! Thanks for the HOW TO collection. That's very helpful.
Q6950; SCL=1254, SDA=1272

 

[2informaticos]

I mean SMBUS_3V3_BATT_SCL/SDA and I2C_PWR_SCL/SDA_R1.
I expect to get values around 0.500, in diode mode.

 

[macfix_hh_25]

Red prob on SMBUS_3V3_BATT_SCL/SDA and black on I2C_PWR_SCL/SDA_R1 = OL
Red prob on I2C_PWR_SCL/SDA_R1 and black on SMBUS_3V3_BATT_SDA= 650 _SCL= OL

Does it mean, Q6950 needs to be replaced?

 

[2informaticos]

I don't think.

"check diode mode to ground at SCL/SDA lines"
What did you check instead???

 

[macfix_hh_25]

I checked again with different multimeter:
Q6950 Pin3 SMBUS_3V3_BATT_SDA to ground in diode mode= 964
Q6950 Pin 6SMBUS_3V3_BATT_SLC to ground in diode mode = 957

In diode mode, I checked before Pin 4 to Pin 3 = 607
and Pin 4 to Pin 6 =1906
(always, red prob on pin 4)

Have I done anything wrong?

 

[2informaticos]

I expected you to check SCL/SDA lines TO GROUND, in diode mode; not over Q6950.
In other words, check diode mode to ground on Q6950 pins 3/6 and 1/4.

 

[macfix_hh_25]

Q6950 pins 3 to ground = 964
Q6950 pin 6 to ground = 954
Q6950 pin 1 to ground = 469
Q6950 pin 4 to ground = 379

With the other Multimeter, I get different readings on Pin 3 (1260) and Pin 6 (1248) to ground. Pin 1 and pin 4 are the same.

 

[2informaticos]

Looks to have a big difference between pins 1 & 4.
Compare readings with good board.

 

[macfix_hh_25]

I don't have a good working board here at the moment. Do you know, what reading should be like?

 

[2informaticos]

OpenBoardData Project

 

[macfix_hh_25]

Numbers from OpenBoardData Project
SMBUS_3V3_BATT_SCLDefaultd0.935
SMBUS_3V3_BATT_SDADefaultd0.937

Would say, very close to my readings in case the value is shown in Kilos?

 

[2informaticos]

I don't understand what you are doing.
I mentioned you big difference between I2C_PWR_SCL/SDA_R1 lines; pins 1 & 4 of Q6950.
U7000, U7800 and U3900 are all connected there; look at page 47.