820-01987 battery is not charging.

[MarcinRdm]

MacBook only started up on power supply. I replaced the batteries. Now MacBook sees battery but won't charge it (0.7A) - I checked on different batteries. Sometimes it downloads 2A for a while but then drops. The power adapter is original. I did a smc reset. Two usb-c ports have 20v

with power supply and battery PPBUS_G3H - 13.06v
only battery 10.3v

 

[2informaticos]

Any of tested batteries was good for sure?

Check Q6950 and its related components and traces.
Also check diode mode and voltage on SCL/SDA lines, before and after Q6950.

 

[MarcinRdm]

The battery is definitely working - I charged it with another macbook A2338. I even did GSX tests - battery is ok.
There is an error on the repaired device - "battery - combined battery test".
SYS_DETECT_L - 0v diode 0.57
SMBUS_3V3_BATT_SCL - jumps 2.9v TO 3.3v, diode the same before and after Q6950 - 0.96
SMBUS_3V3_BATT_SDA - jumps 2.9v TO 3.3v, diode the same before and after Q6950 - 0.98
PPBAT_G3H_CHGR_R with power supply - 13v
PPBAT_G3H_CHGR_R battery only - 10v

 

[2informaticos]

Check ohm resistance over C7020/23.
Does the machine start with charged battery (without charger connected)?

 

[MarcinRdm]

C7020 3.6 m ohm
C7021 68 k ohm
C7072 65k ohm
C7023 65k ohm
Starts normally on a charged battery alone.

 

[2informaticos]

I meant to measure ohm scale between the pins of mentioned caps.
Check schematic, you must get 2 ohm on each one!

 

[MarcinRdm]

I don't have this result anywhere. Can you explain with some exact example. I'm not sure if i am doing it right.

C7020 between pin 1 and 2 - 3.3 ohm
C7023 between pin 1 and 2 - 2.2 ohm

Sometimes there is a moment that for a while it charges correctly immediately after connecting, but it lasts a while.
In the meantime, I replaced the ISL and still the same symptom.
Today even got the same model of a working Macbook and I replaced the motherboard - the same symptom.

 

[2informaticos]

C7020/23 readings look good.

Did you test the board on other shell and still not charging?
I'm not sure which board in which shell you've tested.

 

[MarcinRdm]

I tested every option. Each time the motherboard was the reason for the lack of battery charging.
I tested the board in another working shell and the same thing happened

 

[MarcinRdm]

I'm already running out of ideas.

 

[2informaticos]

How the problem appeared?

Do SMC reset.
Also try DFU.

 

[MarcinRdm]

Suddenly, it stopped charging and worked under the power supply alone.
I reset smc, DFU to - restore. I have the same working motherboard so I can check something else. Do you have any idea master ?

 

[2informaticos]

Compare voltage and diode mode readings around U7000 and Q7065/70 with good board.
Check CHGR_A/BMON w/ and w/o battery connected.

 

[MarcinRdm]

In diode mode everything looked the same. I replaced the Q7065 and the MacBook started to charging. CHGR_BGATE with battery and power supply was around 12v all the time. Should I still replace the Q7070 ?

 

[2informaticos]

If charges now, don't change anything more.

 

[MarcinRdm]

Thanks for your help.