Problem Macbook 2019 16” A2141 no power

[dclass-pro]

I have a strange problem with a MacBook Pro 2019 16” A2141 that won't boot, initially it was shorted The U9080 chip that generates the PP2V5_NAND_SSD1, replaced and now I have the 2.5v together with all voltages 3V 1.8v 0.9v when I plug in the power supply and it passes quietly from 5 to 20v and it starts charging but after a few seconds the absorption goes to 0 and it tries again but nothing happens it doesn't start and the fans don't turn… the battery starts charging but then since it goes to 0 it doesn't load it anymore and so in an infinite loop 😩 I noticed that I don't have the PP3V3_S5 voltage, I didn't understand who generates it but I thought the problem was the PMU, which I changed but the exact same defect.. not nothing has changed.
If I put the MAC in dfu mode, the other macbook sees it and from Apple Configurator if I click on the Restore button, the restore starts and at point 4 out of 4 it crashes and an error comes out.
What can I check? I've been going crazy for days and I can't find the solution.
Thank you all!

[mon2]

Re: Problem Macbook 2019 16” A2141 no power

Is the power adapter the original or at least rated to support this macbook?

Suggest 100W Type C and see if the fault remains.

Do you have a thermal camera? Some component may be heating up and causing this loop.

[dclass-pro]

Re: Problem Macbook 2019 16” A2141 no power

I'm doing the test with the bench power supply and the BY-3200 adapter, but it doesn't absorb even 1A so it shouldn't be a power problem... I have the thermal imager but it doesn't heat anything.
If I turn on the motherboard without the battery I have an absorption of 100mA/110mA, is this normal?

[mon2]

Re: Problem Macbook 2019 16” A2141 no power

I know that some macbook models do require a battery to boot. Not sure of the exact models but Tim @ TCRS (youtube) specifically mentions this key detail.

May be worthwhile to locate his video that mentions the same - believe it is in the early part of the video.

[Aliseo]

Re: Problem Macbook 2019 16” A2141 no power

Hello dear, you have a problem with the PMIC, replace it and check.
I had the same problem on an a2179, an air and I fixed it

[dclass-pro]

Re: Problem Macbook 2019 16” A2141 no power

ok i will try to check from the video, thanks for the advice, anyway even if i connect the battery i dont have the pp3v3_s5... i tried through dfu mode but this is the error i get "Error AMRestoreErrorDomain 6 - Faliedto handle message type StatusMsg), I don't want there to be some problem with the NAND... but I can't figure out who generates the PP3v3_S5 and when it should be generated..

[dclass-pro]

Re: Problem Macbook 2019 16” A2141 no power

Ciao caro, hai un problema con il PMIC, sostituiscilo e fai delle verifiche.
Ho Aavuto lo stesso problema su un a2179, un air e ho risolto

hi which one do you mean exactly by PMIC ? I changed the PMU and nothing changed

[SMDFlea]

Re: Problem Macbook 2019 16” A2141 no power

Hello dear, you have a problem with the PMIC, replace it and check.
I had the same problem on an a2179, an air and I fixed it

english please https://translate.google.it/ In inglese per favore
.

[dclass-pro]

Re: Problem Macbook 2019 16” A2141 no power

"Originally Posted by Aliseo View Post
Hello dear, you have a problem with the PMIC, replace it and check.
I had the same problem on an a2179, an air and I fixed it"
hi which one do you mean exactly by PMIC ? I changed the PMU and nothing changed

[anhbanxoi]

Re: Problem Macbook 2019 16” A2141 no power

Check the resistant between PPBUS and PP2V5_NAND_SSD1. I think the ssd is gone.

[dclass-pro]

Re: Problem Macbook 2019 16” A2141 no power

Hi, the resistance between PP2V5_NAND_SSD0 and ground is 6 ohm, but when I power the card the 2.5v is fine and doesn't become 0 it remains very stable. the resistance between PPBUS_G3H and PP2V5_NAND_SSD0 is 2 Mohm

[reformatt]

Re: Problem Macbook 2019 16” A2141 no power

If you had a short on PPBUS_G3H due to U9080, then the usual failure pattern is application of 12V onto a 2.5V rail. Damage to the NAND's is highly likely in that event. 6 ohms sounds pretty low to me.

[dclass-pro]

Re: Problem Macbook 2019 16” A2141 no power

Do you advise me to unsolder the nands and see if the machine turns on?

[zpi]

Re: Problem Macbook 2019 16” A2141 no power

Machine will be in power on loop without nands same as you have now, your boards behavior is same as bad nands, just had same case, but one of two nand power rails was shorted by nand. Check both coils near u9080

[dclass-pro]

Re: Problem Macbook 2019 16” A2141 no power

all coils both near U9080 and near U9580 are good

[zpi]

Re: Problem Macbook 2019 16” A2141 no power

I mean check resistance to ground on these coils.

[dclass-pro]

Re: Problem Macbook 2019 16” A2141 no power

it is about 2k between coils near U9080 and ground (but nands are not mounted and 6ohm between coils near U9580 and ground nand soldered)

[zpi]

Re: Problem Macbook 2019 16” A2141 no power

Lift one side of L9580 and L9581, and check if 6ohm is on pin 1 side or pin 2 side (nand side or controller side)

[dclass-pro]

Re: Problem Macbook 2019 16” A2141 no power

I confirm the 6ohm are nand side

[zpi]

Re: Problem Macbook 2019 16” A2141 no power

Thats to low, if you have thermal camera. Yo can inject 1-2volts to see bad nand.