MacBook Pro 2018 - A1990 Dead - not charging - only 5V

[robka]

Hi,

my MacBook Pro 15" 2018 Touch Bar (A1990) doesn't charge anymore. Board# 820-01041-A

I'm not experienced in diagnostics, but I want to try to solve the problem with your help, because every local shop charges around 600€ (650 usd). Which is the value of the whole Macbook.

The Macbook was charging when suddenly the "charging sound" appeared every other second for around 4-5 times.
After that the Macbook was dead. It isn't charging anymore.

The USB-C Port where the charger was plugged is burned. Also The Cable and the power adapter. So probably this had a fault.

I checked the voltage and it's only pulling 5v on each port.



Can somebody tell me, where and how to check first with a multimeter?

Edit: check F7000 & F7001 - ok

Thank you

[mon2]

Remove all power -> meter in resistance mode -> measure the resistance to ground @ F7000 or F7001. If the resistance is not low -> meter in voltage mode (DC setting; 20v or higher) -> measure the voltage to ground @ F7000 or F7001.

Post each measurement.

local shop charges around 600€ (650 usd)

Thieves.

[robka]

Remove all power -> meter in resistance mode -> measure the resistance to ground @ F7000 or F7001

both won't dial in. The value is increasing and decreasing all the time.

[kevingill]

Check power rails in power up sequence.
Use this site as a guide for your board.
https://openboarddata.org

[robka]

Check power rails in power up sequence.

I‘m not sure if I understand right. I should check power rails when I‘m booting? The MacBook won't boot. It's dead - probably the battery is empty also.
sorry, English isn't my mothertongue and therefore some words are probably missing.

Use this site as a guide for your board.
https://openboarddata.org

Unfortunately, I can't do anything with it because I don't know how to use it.

[robka]

nobody?

[mon2]

Post the range of the resistance being observed from post # 3. Need measured values to understand if there is a short on the board or not.

[Stephen]

nobody?

Can you show us the type of MacBook Charger you are using? I am curious about that first hand. We do not want you to continue using a KNOCK OFF NON OEM charger, most of these issues could arise from hot plugging, however, knock off chargers are known to frying the port even if you plug it in correctly and not send the voltage down the wrong rail. If it doesn't have an Apple Logo on the brick chances I would do is throw that charger away and get a used OEM one online. Not a new one from Amazon or wherever. Secondly, if one port is fried and causing issues but all the other ports are working, I would highly suspect that individual port is the issue and I would replace that USB C chip is fried and needs to be removed and replaced with a good one.


"because every local shop charges around 600€ (650 usd). "

OUCH! You can get a good working A1990 board for half that price I believe, however a board repair at our shop costs $300 for 2018 and above. 2017 and below A1707 and A1706 boards $150.00 (not going into data recovery) if you just need it fixed to retain the information.

[robka]

Remove all power -> meter in resistance mode -> measure the resistance to ground @ F7000 or F7001. If the resistance is not low -> meter in voltage mode (DC setting; 20v or higher) -> measure the voltage to ground @ F7000 or F7001.

Post each measurement.



Thieves.

F7000 & F7001 0 Ohm

F3000 & F3001 5v

[robka]

Can you show us the type of MacBook Charger you are using? I am curious about that first hand. We do not want you to continue using a KNOCK OFF NON OEM charger, most of these issues could arise from hot plugging….

no knock off.
I‘m using the original delivered charger.

[mon2]

What is the current draw at the 5 volts by the power adapter?

for resistance checks, be sure there is no power. Meter in lowest resistance scale. One probe on the fuse F7000. Other probe to ground. You still have 0 ohms measurement?

[robka]

Draw is always 5v.

Resistance was checked without power plugged in.

[mon2]

Ok but what is the current draw? Or you can post a pic of the meter face to show the readings. It should be in mA or A (milli amps; Amps, etc.). This will help to diagnose the case.

[robka]

Ok but what is the current draw? Or you can post a pic of the meter face to show the readings. It should be in mA or A (milli amps; Amps, etc.). This will help to diagnose the case.

I'm sorry.
It bounces between 0.048, 0.321 and 0.459 A @ 5V

[mon2]

Ok. Would you say the current draw is cycling from 0.048A = 48 mA to 0.459A = 459 mA and then back to 48mA and repeats? Then this is power cycling. Can you confirm this?

[robka]

Yes, that's correct.

[mon2]

Is this the same pattern for each USB Type C port? Do check by flipping the adapter cable head by 180 degrees as well. Before doing this, unplug the power adapter -> perform the switch to the other side of the type C blade connector and then power up with the external adapter. Personally do not trust the removal and insertion of this interface while the power is 'hot' from the power adapter.

Perhaps one of the type C ports is stable and does not power cycle / loop? As requested, test topside and bottom side of the power head.

[robka]

https://imgur.com/a/UcIicwK

please see attached photos and descriptions for values.

[mon2]

Concerned about the USB Type C meter. There are silk screened markings for 'INPUT' and 'OUTPUT'. Is this meter not bidirectional? This may be a factor in the review. That is, the power adapter side should be the INPUT and respectively, the logic board should be the OUTPUT.

The contacts look dirty -> use IPA (alcohol) and a Q-tip / cotton swab and clean each side of each USB Type C connector.

[robka]

Concerned about the USB Type C meter. There are silk screened markings for 'INPUT' and 'OUTPUT'. Is this meter not bidirectional? This may be a factor in the review. That is, the power adapter side should be the INPUT and respectively, the logic board should be the OUTPUT.

just verified the function with my M2 MacBook Pro. It shows 2.2amps @ 20v.

The contacts look dirty -> use IPA (alcohol) and a Q-tip / cotton swab and clean each side of each USB Type C connector.

it's burned