820-02098 - Starting up but amperage limited when charging

overshoot

Member
Hello,

Working on an 820-02098 (M1 14" Pro) that had a previous repair attempt and some missing USB-C chips.

Long story short, I've replaced all the USB-C and ROM chips from 2 donor boards since each donor board did not have them all (820-02098 and 820-02443).
I believe these boards had good USB-C chips but uncertain.
Previously I would not get PPBUS_AON when connected from some USB-C ports but now I do from all of them, including LDOs.
However I am not getting 20V, just 5V with about 120mA, fluctuating.
I have also replaced the CC protection chips (on UF400 and UF500) since these were re-balled poorly and killed one of my donor CD3217B12.
I am now trying to revive/restore the board to see where the log would fail but the Mac won't go to DFU or won't be seen from the host Mac.
I am however getting 20V with 100mA when the board is in its housing, battery connected.

That was yesterday.
I left the machine overnight plugged to the charger and this morning the laptop was on, with the battery partially charging.
Yesterday as soon as I was pressing the power button or the trackpad, the charger would reset itself, so I am thinking there is some kind of limitation in the amount of power (amperage) it can take.

Can a restore fix potentially an issue with the ROM software mismatch?
Any idea what could be going on please?
 
Last edited:

overshoot

Member
Using macvdmtool, I can put the Mac in DFU (it seems) as the Mac shuts off.
I can also reboot it using another macvdmtool command, however the host Mac won't see the device so I can't restore it.
 
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