A2442 820-02098 5V 0.25A -> 0.05A Blown CD3217 and TPS62180 ELC180

[2informaticos]

All CD3217 chips must be present, to switch power input input to 20V.
If your chip is B12, then buy it form Aliexpress, if available.

However, I recommend you to find what's the problem with the short on TPS62180 area.
It may be used as 3V3_G3H_RTC generator in other boards; 01041, for example.
Not worth to work on USB-C area to find not repairable issue on other place.

Unfortunately, schematic not available for this board.

 

[it-solve]

Probed all coils and bigger caps, could not detect any shorts. Not sure where those lead to, but don't have short to ground. These are the readings



Two 0.4 pins are shorting to each other, but are 0.4 diode mode to ground. I thought these are phases, but seems to be VIN based on datasheet
Looking at A1990 TPS62180, it seems to join inputs together. Looks ok on the board based on the reference design?


Chip itself shorts VIN2 to Ground only




I can grab TPS62180 from A1990 I have laying here, seems to be 0.5 pitch. Also seems to be present on A1989, A2159 and new iMacs too

 

[2informaticos]

OK, I now understood.
You didn't see first that both coils are tied together.

Then if no short, replace TPS62180 and check what happens connecting known good batery (holding some charge).

 

[it-solve]

Replaced the TPS and no short around it. Reading seems legit.

Firing with the battery will be trouble though, as I measure 0V across batt terminals and is not spinning when in the case. Also no voltage across the AON fuses

Seems like need to get CD3217B12 and see how it goes

I have a stencil for these, but they seem tricky to reball.

 

[2informaticos]

Did you connect the battery data cable too?
Maybe this battery doesn't hold charge at all.
Do not connect charger.

Many times boards can turn on with battery, even have problems on USB-C areas; may not be the case now.

 

[it-solve]

YEah connected both the data cable and battery thingy. Haven't connected a charger.

I don't have another battery/case of A2442 to test. Only option seems to be a CD3217 replacement?
Unless there is a way to jumpstart these batteries, but highly doubt it.

 

[2informaticos]

Then need to change the CD3217 chip.
Be sure to get one with same code termination.

 

[it-solve]

Ok managed to turn it on in the case with replaced CD3217B12. Initially, I've got 5V 0.9A and range light but not showing charging icon. Reattached Magsafe3 multiple times and now I get 20V 0A.

Replaced twice CD3217B12 still not detecting charger,

I assume you refer to B12 as termination.

 

[2informaticos]

Yes, good if is same as original.

Did you test with both charger and battery connected?

 

[it-solve]

Yes both via all USBCs and magsafe3.

Can it be something with the charging ISL's? How do you trace it without a schematic?
Based on - https://repair.wiki/w/A2442_2021_14"_MacBook_Pro

PPBUS_AON without BATT- 0V
PPBUS_AON - 12V

 

[2informaticos]

Check if parts of 820-02020 schematic help somehow; maybe 02016 also.
Any reaction on power rails pressing power button, with battery connected?

 

[it-solve]

Now it turns on with battery and works well. Just can't get it to charge.

Trying to figure out the charging circuit.

 

[2informaticos]

That means you still have problems with USB-C areas...

 

[it-solve]

Replaced 3 different CD3217 chips on the place of this burned one, albeit they all came from a donor board. I still can't get them to switch to 20V when USBc is connected.

Other 3 ports seems to go 5V 0.25A -> 0.005A when connected. While this one with burned CD3217 stays at 5V 0.003A and won't react to the charger.

I am thinking to take one of the other "functioning" CD3217, reball and place here to see if it's gonna flip to 0.25A to confirm the surrounding area is fine. As a sanity check of my reballing maybe?

 

[it-solve]

USBc ports were cleaned and I am testing with a clean one on the desk.



Cross matched the CD3217 with others and the readings are the same. Here are the readings of the CD3217 I worked on (measurements are on the chip side legs).

It is a bit odd that I have one resistor and one capacitor which reads Ground on both ends (took it out and measures fine). The ones marked with 0



Also, one resistor is 0L. Wonder if it is an issue with a pad. I don't have any 0L resistors on the reference CD3217s

It is hard to match with others as each has its own layout

 

[2informaticos]

Without schematic/boardview, is almost impossible to know where which component is connected.
However, the OL reading may point to broken trace, or bad solder under CD3217 chip.
Did you check the traces before soldering another chip?
Once chip is removed, you may see which pad corresponds to that OL reading.

 

[it-solve]

The issue with OL was a bad pad on this particular CD3217, but others I have tested were ok. The pads on the board are fine, so far. Not sure how many more attempts I can do before I rip at least one away.

I am suspecting the Shorted Cap I measured. So I lifted up the NoMarking BGA IC and the short has gone. Measuring on the pads of that IC I get 27Ohm. Isn't that too low to be across a cap?


I could not find any other schematic which is not in BVR format to try to identify this chip (Still can't justify buying flexbv).
I have this unknown chip around all the CD3217's, and the caps around do not have such low impedance. May be related? This part of the board had lots of corrosion around the UBS-C connector, while none was on this side of the board.

Moved that Resistor to measure its value, and is measuring 0Ohm when not connected while pads don't measure short.

 

[2informaticos]

If you don't get short on equivalent cap near other CD3217, then that non-marked chip is bad.
The problem is to identify it now.
Look at it under microscope with different light angles.