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Looks like skipping over portions of the power on sequence that I assumed were required for later sections was a bad decision. The first line with an issue is actually PMU_PVDDMAIN_EN, P3V3MAIN_PGOOD and subsequent rails in that section do not come online. The last time I saw a failure at...

Yes, all of the voltages in the SSD 4 LANDING and SSD 2 LANDING sections of the power on sequence document are fine. It's possible that SSD0 got zapped with PPBUS, but there's no shorts, so it feels premature to call off recovery efforts based on that. How would I go about getting a...

Ran out of other ideas so I gave a DFU revive a try. Error below, I've found minimal information on this code. Looks like it's now auto booting to dfu.

No, this is a data critical job and I’m concerned that dfu could negatively impact the data, or complicate the repair by necessitating another dfu revive after everything I try. What’re your thoughts?

820-01700-05 light liquid damage, concentrated on U9580, U9500, U3100, and U3200. Reflowed U3100, U3200. Reballed U9580, U9500. Verified 20V on all 4 USB-C ports. Current steadily climbs until peaking at 0.31A 20V before suddenly dropping off to 0.01-0.03A 20V, and remains steady there...

Update: I verified with a working board, removing U9080 caused the behavior described above. I will be proceeding with the SSD transplant.

Thank you for your insights and advice on this project! My hope is that because the T2 can’t find its firmware, the system automatically resets after 15 seconds and that’s why I see fluctuations in PPBUS and other rails. So last question - Any idea if it’s normal to see some sort of an...

While I'm comfortable flipping NANDs, donor boards with 6x NANDs in a high capacity SSD configuration are extremely expensive, so I'm very hesitant to take the NANDs off my $275 donor board unless I'm confident this is going to work. I've now removed all six NANDs, and replaced U9580 with U9080...

Well, I think I figured it out... This board is a trip. Board was sitting across the room with USB-C power connected with the same behavior as before I removed and replaced the passives, when U9580 suddenly exploded, and the right 12 pads were completely vaporized. After removing the remains of...

No change with C9582, after removing the original I verified the correct capacitance of 2.2nF R9580 and 81 have the correct values when removed from the board and tested externally Is there any way that tinkering with the feedback voltage divider could solve my cycling problem?

C9582 and C9585 are not shorted, capacity test in circuit didn't work but I can pull either if that's helpful. R9583 is 10 ohms as expected. R9580 and R9581 both measure 150K but show as 475K and 221K on my 820-01700-A schematic. Could this be due to differences between the 820-01700-A and...

Yes, both sides of L9581, and every other spot I've probed PP2V5_NAND_SSD0 show the exact same behavior. To get more specific on the timing, PP2V5_NAND_SSD0 is 3.07V for about 15 seconds, then drops to 1.51V for about 2 seconds, and then repeats in a loop. This isn't the output of the buck...

I have not installed any donor NANDs yet. Just removed the shorted NAND and observed that somehow I'm getting 1.5 to 3v on a 2.5v line. I'm familiar with the need to transfer a complete set of NANDs from a select list of compatible boards and match up the clock request line IDs and not doing...

Additional note: Before removing U9400, the board consumed 0.01A at 5V when powered, now it consumes 0.110A at 20V, so I feel confident the NAND was the issue, but I don't understand the present situation.

Finding donor NAND's for this board has been quite the saga, but now I'm afraid it might have been in vain. I removed U9400, the NAND that was getting warm, after which PP2V5_NAND_SSD0 still has a diode reading of 0.018, which seems low to me. This is the exact same value as it had before...

Resolved... My CD3217 stencil finally arrived... Took off the CD3217's from MS, reballed the originals, and the board works again. &$*@^$*! The MS ones were soldered properly, and the top serial number matched exactly. Won't be using those again.

Nothing SSD related has power, and I don't see any shorts. Liquid didn't touch U9000 or U9080, SSD0_VR_2V5_EN is 0V, PPBUS_G3H_SSD0 is good. I started working through this document to try and identify what power rails aren't present...

Any other advice for this one? Thank you!

Yes, currently 5V 0.25A stable on all ports. Before applying power to anything I replaced one CD3217 that was clearly hit by liquid, after that one port was looping and the other three were stable. I found a bad resistor near the CD3217 ROM and after replacing it, the fourth port stabilized...

Looks like no. I Connected the power button, keyboard, trackpad, screen, and USB-C port flex's to the board, and tried holding "T" while booting the board in every configuration I could think of with the battery and other mac connected or disconnected. Not sure what to expect when the device is...