820-0085-a no power/ no charge

[pantsos]

Hey there,

I have a MacBook 820-0085-a that was working perfectly, after keyboard replacement the MacBook would not charge any more. As we speak the battery might be completely dead. I think that this MacBook need a battery to boot up.

I have a very limited experience with newer MacBooks. If anyone would suggest where to start taking measurements or testing, I would appreciate it.

All I know is that the MacBook was working perfect before the keyboard switch.
A tech confirmed that he used a universal charger.

Thank you

[mon2]

I think you mean 820-00850 logic board.

Do you have a USB Type C meter? To confirm, even after the keyboard was replaced, only the battery would not charge?

Remove all power. Meter in resistance mode. Measure the resistance to ground of each pin on the battery connector. It is ok to remove the battery and then probe the pins on the battery connector that is on the logic board.

No battery / no power adapter during these tests. You can use the metal shield for the ground on the logic board.

Pins # 2 & # 3 are of the most interest. These are the SDA / SCL lines which are the SMBUS / I2C lines used to communicate with the battery BMS inside of the battery pack.

Post each measurement.

[mosfetratus]

It needs to be fully assembled so the pins on the board are grounded. Otherwise board will act as dead.

[pantsos]

I think you mean 820-00850 logic board.

Do you have a USB Type C meter? To confirm, even after the keyboard was replaced, only the battery would not charge?

Remove all power. Meter in resistance mode. Measure the resistance to ground of each pin on the battery connector. It is ok to remove the battery and then probe the pins on the battery connector that is on the logic board.

No battery / no power adapter during these tests. You can use the metal shield for the ground on the logic board.

Pins # 2 & # 3 are of the most interest. These are the SDA / SCL lines which are the SMBUS / I2C lines used to communicate with the battery BMS inside of the battery pack.

Post each measurement.

Thank you for getting back to me.
You are correct the model is 820-00850.

after the keyboard replace whoever replaced it said that it would be possible to turn it on, but didn't charge.
me I never saw the MacBook turning on.

Yes I do have usb c meter tester.
i think on the downside of the usb c port have different behavior that the top ones.

Measuring the battery in diode mode connector it seems that everything is good.

j6951

Pins:
1)0,5
2) 0.8
3)0.8
4) OL
5) GND
6) OL

[mon2]

What is the voltage to ground on pin #2 of the battery connector? Red probe on pin # 2; black probe to ground.

Repeat for pin #3 of the battery connector. Post each voltage measurement.

What voltage and current draw is showing on your USB Type C meter? It should be 20V if working properly.

[pantsos]

What is the voltage to ground on pin #2 of the battery connector? Red probe on pin # 2; black probe to ground.

Repeat for pin #3 of the battery connector. Post each voltage measurement.

What voltage and current draw is showing on your USB Type C meter? It should be 20V if working properly.

The board is out. Plugged in with the charger only, pin 2 and pin 3 have the same behavior.

rapid changes in number that I can not even read, but every 2-3 seconds I see 0.000 and then playing and mostly i think there is a short somewhere.

USB C meter shows 5V and amps starting 0.19A goes to 0.49A and then hangs at 0.19 and then goes to 0.50A

if I plug it in the second plug USB C port, 0.00 I see 0.31 and then again 0.00. I

[pantsos]

I guess my issue is not that simple?

[mon2]

Carefully measure the voltage (meter in DC volts mode @ 20v or higher scale) of PPBUS_G3H @ fuse F7000. Check both sides of this fuse. What is the voltage? Is it stable?

What is your USB Type C meter reporting for the adapter voltage? Adapter current being used by the logic board? Post all observations. For a normal board to boot, the adapter voltage should be @ 20 volts.

[pantsos]

This board has 4 usb c ports. Each side, the top ones starting from 3V and then slowly goes down to 0.3V.
the bottom ones is not stable. It plays from 8-10V all the way down and then up again in 1-2 seconds.

type c meter is the SATECHI.

The way I test it is the board is completely out and only connect the usb c port while plugged with the usb c meter and then the original charging adaptor

[mon2]

Each side, the top ones starting from 3V and then slowly goes down to 0.3V.
the bottom ones is not stable. It plays from 8-10V all the way down and then up again in 1-2 seconds.

1) Is the power adapter the original and recommended model for this laptop?
2) The USB-C meter is reporting 3v down to 0v3? What is 8-10V and then power cycles? Is this the voltage measurement @ fuse F7000 = PPBUS_G3H to ground?

[pantsos]

1)Yes it's the original 61W that comes with the laptop.

2) The USB meter is stable at 5V and I see 0.15A and when I check voltage on F7000 the voltage starts at 2.9V and then slowly goes down.

The bottom port I see again 5V and then power cycles 0.00A and then 0.45 then 0.35A then back to 0.00

For these measurements I use DC on my multimeter black probe to ground and red probe on F7000 on both sides

[mon2]

Remove all power. Meter in resistance mode (not diode mode). Measure the resistance to ground at F7000 (check both sides). Post the measurement. Suggest to flux and remove F7000 off the logic board.

Then power up again. Measure the DC voltage to ground of F7000 @ pcb pad of the removed fuse. Do you now have a stable voltage at PPBUS_G3H ?

[pantsos]

Power is off. Multimeter in resistance mode with the F7000 removed. One side I get 3.9 MΩ. Other side I get 16.40 MΩ.

Power on with the fuse still removed DC voltage one side 0.100V stable - other side 0.316V stable

[mon2]

The resistance is good for both sides of the removed fuse F7000.

It plays from 8-10V all the way down and then up again in 1-2 seconds.

Where do you observe this voltage range?

[pantsos]

Bottom usb c ports when I connect power measuring in DC with F7000 on the board.

[pantsos]

Just checked again the bottom usb c port power in with f7000 removed - one side DC voltage is 0.005V and the other side is 12.30V

top port with f7000 removed power in in DC one side is 0.005 and other side is 1.420V