Multiple A2442 MacBook Pros 14" with the same charging issues

[Stephen]

Update, I reflowed the chip and now the caps are staying consistent with their respected readings...doing a little more digging.

[Stephen]

Plugged the battery in stuck at 20 volts 0.00amps still getting no charge via USB C. But did discover that USB C CD3217B12 chip was acting weird, reflowed brought it back to life it looks like... PPBUS_AON drops to 11.3 volts.

[mon2]

PPCHGR_VDDA = Voltage dropping. went down from 5volts down to 1 volt and still dropping.
PPCHGR_VDDP = 5volts and dropping..
PPVBAT_AON_CHGR_REG =1.5volts and not dropping any further

ISL is not being powered.

Ignore - late reply to the above.

[mon2]

Ok - nice!

But 0A means still something wrong in the power path.

[Stephen]

Ok - nice!

But 0A means still something wrong in the power path.

Yes, turns on, but won't charge. ISL9240 allows the computer to turn on, also this is a brand new chip on the board so it turned on without issue once it was replaced...charging issue still being a punk.

I have a question, would the 5Volt Regulator chip have anything to do with the charging issue? I am talking about UF800 (this chip was liquid damaged with corrosion but didn't seem like it was bad since the corrosion came off without an issue and all the caps and resistors look good.

[mon2]

What is the voltage to ground you are measuring on LF800? (PP5V_S2SW_USBC01) Should be ~5v2.

[Stephen]

I did noticed that CHGR_AUX_DET_3v3 is not showing any voltage at Q5216. Is this normal?

[Stephen]

What is the voltage to ground you are measuring on LF800? (PP5V_S2SW_USBC01) Should be ~5v2.

No voltage present.

[Stephen]

Hey mon2 do you have any idea what this means. Sorry to bother you, you been a great help as always

[mon2]

Measure the voltage to ground of:

PPVIN_5VUSBC01_ISNS
P5VUSBC01_EN_R

[Stephen]

PPVIN_5USBC01_ISNS = NO VOLTAGE PRESENT
P5USBC01_EN_R = NO VOLTAGE PRESENT

[mon2]

This implies that PPBUS_AON = 0v. Is this correct? PPBUS_AON was not 0v at the start.

[Stephen]

PPBUS_AON is at 12volts exactly while plugged in but those areas have 0 volts present when PPBUS_AON is at 12 volts. I am missing .30 volts which indicates some issue present. I know once I hit that 12.30+ volts I repaired it. But I checked all the resistors and they checked out working and their resistance was in normal standing. I replaced one bad resistor in question but that didn't solve it. So I am still stuck in limbo. I am certain once we figure it out this will solve this problem for all future repairs. Could use this as a reference as well.

[mon2]

Remove all power. Meter in resistance mode. Measure the resistance across RD761.

[Stephen]

RD761- 0.1 OHMS (I check it needs 0.002 ohms)

[mon2]

This may be just the inaccuracy of your meter but you can always replace it to test. However, note that the voltage should not drop to 0v across this resistor.

Confirm if you have a voltage on the other side of this resistor. Perhaps turns off due to the larger resistance at this junction.

[Stephen]

This resistor has 12volts so voltage is present on this resistor (RD761

[Stephen]

I checked the voltage on CF801 and so forth and there is voltage present. I am going to replace my multimeter probes now.

[Stephen]

Voltage Present at 12Volts on PPVIN_5USBC01_ISNS = 12Volts
P5USBC01_EN_R - No Voltage present still

[mon2]

You mean P5VUSBC01_EN_R? Full name is important else this turns into 'Where is Waldo?'.

Measure the voltage to the gate to UF840. Is it being powered? Measure @ CF840.