820-02098 not charging help me

[Joyoungjae]

Dear friends
Merry Christmas

I came out to work briefly today as well.

I'm not unhappy haha


I received a MacBook Pro A2442 water damage.

When I connect the charger, it keeps turning on and off and the voltage indicator blinks.

When the charger is removed, the power turns on and remains on with the remaining charge in the battery.
After submersion cleaning, the submerged Q5240 and UG800 (elc180 power ic?) were replaced.

Still, the symptoms are the same, so I'm trying to replace the charging IC, but I'm curious if it's meaningful.

If that's correct, the charging IC (u5200) I have is ISL9240HI, but the chip installed in the MacBook in question is ISL9240HIB3.
I wonder if I can just use it.

Thank you for reading and have a nice Christmas

[mon2]

Hello. Merry Christmas - ours is later tonight.

For now, do not worry about this very tiny WLCSP packaged device. It is not fun to replace and may raise more issues than the current fault on the logic board. Unless 100% confident this device is faulty, do not mess with it. The part is available on Aliexpress.

Suggest:

1) purchase a USB Type C meter and insert it between your power adapter and this logic board. The digital display on the meter will offer details on the power delivery contracts being selected by the logic board. For a normal boot and charging process, the power delivery contract should be @ 20V (not the power up default of 5 volts). If you have this tool - do share the details of the display.

2) Remove the battery. Use only the power adapter. Carefully measure the voltage to ground @ F5200 or F5201. What is the voltage measurement? Is it power cycling? At this point of test, the ISL9240 is the producer of this power rail in that the power delivery controllers have instructed the external power adapter to spit out 20V. Then this regulator acts like a buck regulator (high input voltage to lower downstream voltage) and should output a voltage in the ~12 to 13 volt range. The exact voltage is important to know to determine at which stage of the power on cycle the logic board is in. If this voltage is not stable, then this leg of the circuit needs to be reviewed.

[Joyoungjae]

!!!!!- thank

[Joyoungjae]

!!!!!-

감사하다

[Joyoungjae]

Hello. Merry Christmas - ours is later tonight.

For now, do not worry about this very tiny WLCSP packaged device. It is not fun to replace and may raise more issues than the current fault on the logic board. Unless 100% confident this device is faulty, do not mess with it. The part is available on Aliexpress.

Suggest:

1) purchase a USB Type C meter and insert it between your power adapter and this logic board. The digital display on the meter will offer details on the power delivery contracts being selected by the logic board. For a normal boot and charging process, the power delivery contract should be @ 20V (not the power up default of 5 volts). If you have this tool - do share the details of the display.

2) Remove the battery. Use only the power adapter. Carefully measure the voltage to ground @ F5200 or F5201. What is the voltage measurement? Is it power cycling? At this point of test, the ISL9240 is the producer of this power rail in that the power delivery controllers have instructed the external power adapter to spit out 20V. Then this regulator acts like a buck regulator (high input voltage to lower downstream voltage) and should output a voltage in the ~12 to 13 volt range. The exact voltage is important to know to determine at which stage of the power on cycle the logic board is in. If this voltage is not stable, then this leg of the circuit needs to be reviewed.

Thank you so much for your kind reply.

First of all, I skipped a lot of things and asked questions.

To be precise, I took a voltage meter and plugged the charger into my MacBook. It switches well up to 20v, but the voltage switch turns off, turns on again, and repeats turning off again when it shows 20v.

So, if I remove the charger, it boots normally. Currently, it turns on because there is still charge left, but if it is discharged, it will not be charged and will not be used.

So I short-circuited the battery and plugged in the charger with only the logic board in place, and it stayed at 20v just fine. In conclusion, pulsing symptoms appear when the charger is connected.

I'm not good at English, so I use a translator...
I'm worried that what I'm trying to say will be heard well.

Anyway, thank you, friend. What do you think?!

[mon2]

Ok. Issue could be a leaky mosfet in the power path to PPBUS_AON. That is, either the power adapter OR battery must power PPBUS_AON - not both.

Remove all power / disconnect the battery. Meter in resistance mode.

Measure the resistance of the mosfet @ Q5265 (battery mosfet)

Measure:

source (1-2-3) & drain (5-6-7-8)
source (1-2-3) & gate (4)
gate (4) & drain (5-6-7-8)

Post each measurement. We are checking for a low resistance which usually means the mosfet is defective.

[Joyoungjae]

Ok. Issue could be a leaky mosfet in the power path to PPBUS_AON. That is, either the power adapter OR battery must power PPBUS_AON - not both.

Remove all power / disconnect the battery. Meter in resistance mode.

Measure the resistance of the mosfet @ Q5265 (battery mosfet)

Measure:

source (1-2-3) & drain (5-6-7-8)
source (1-2-3) & gate (4)
gate (4) & drain (5-6-7-8)

Post each measurement. We are checking for a low resistance which usually means the mosfet is defective.

hellio sir

I'm not sure if I understand it correctly, but if you measure Q5265 from 1, 2, 3 to 5, you get 0.710m ohm.

And if you take 4 to 5, it is measured as 15.42m ohm.

Is it true that you want me to take a picture like this?



After measuring 1, 2, 3 to 4,

It comes out at 5.7 m ohm!!

I have the same board, so I took a picture of another board and got 11.2m ohm. Is this the problem??

[mon2]

Perform the same measurements on the good board for Q5265 so we can compare. Post each measurement. Only the first reading looks low (1-2-3 and 5-6-7-8).

[Joyoungjae]

Perform the same measurements on the good board for Q5265 so we can compare. Post each measurement. Only the first reading looks low (1-2-3 and 5-6-7-8).

thank you sir

When taken on a good board, only 1, 2, 3 to 4 show different values.

Are you talking about measuring from ground to point?

I recorded the resistance values in the MOSFET using 1, 2, 3 points and 4 points.

Did I understand it well?

[mon2]

No, not to ground. Just across the mosfet pins. The good board is also ~700k ohms for source to drain pins?

how did you short circuit the battery to run the logic board? Bypassed q5265?

[Joyoungjae]

Perform the same measurements on the good board for Q5265 so we can compare. Post each measurement. Only the first reading looks low (1-2-3 and 5-6-7-8).

sir
Just in case, I measured it again and this time the resistance value was the same as the normal board. Is my tester weird?


Yes and it outputs ~700k ohm

[Joyoungjae]

No, not to ground. Just across the mosfet pins. The good board is also ~700k ohms for source to drain pins?

how did you short circuit the battery to run the logic board? Bypassed q5265?

no

Turning on the MacBook works normally when the charger is unplugged, so you can boot it up without the charger connected.

Sorry, I guess I misrepresented something in the question.

Can I ask you a question via message? I'm worried about whether I understand what sir is saying.

[mon2]

Is the charger the original from Apple? What is the power rating of this adapter? If the power adapter is under rated, it will power cycle.

if you remove the battery and use only the power adapter, what is the voltage of PPBUS_AON?

do you still have a power cycling? Concerned about the replaced dual mosfet. Soldered ok?

Best to continue the investigation here in this forum so other techs can assist. About to watch some Netflix. Ps: my brother is obsessed with the many tv series from South Korea on Netflix. He claims much better writing than Hollywood.

[Joyoungjae]

Is the charger the original from Apple? What is the power rating of this adapter? If the power adapter is under rated, it will power cycle.

if you remove the battery and use only the power adapter, what is the voltage of PPBUS_AON?

do you still have a power cycling? Concerned about the replaced dual mosfet. Soldered ok?

Best to continue the investigation here in this forum so other techs can assist. About to watch some Netflix. Ps: my brother is obsessed with the many tv series from South Korea on Netflix. He claims much better writing than Hollywood.

First of all, we've completed the repair.

Sir's kind explanation made me take a slow look at what I didn't see.

As a result, I rediscovered what I missed from the beginning.

I found a fine short on LDO circuit lines around cd3217.

It made me realize again by tracing back from the UG800 where corrosion was first seen due to flooding.

When I do repairs, I get stuck in one place and miss it like this, but the things you advise me felt like I was repairing together and it helped. Thank you.


P.s / Oh really? I happened to watch Concrete utopia last week and it was fun