Looking at the schematic that PPVIN_2V7NAND_LB line comes from PPBUS_GSH so as a test I ran a jumper from the closest source of PPBUS_GSH (pin 1 C6582) to the testpad and the SSD was now detected. However there was no continuity between that TP and pin 43 (PPVIN_2V7NAND_LB) of J9600. I had previously checked the integrity of the Lifeboat connector at J9600 and all was good there. I had one case where no damage in the R9350 area but upon checking, there was no PPVIN_2V7NAND_LB at the TP above R9350.In one case, a short circuit caused by C9416/Q9401/U9400 due to U9400 circuit failure.When not liquid damaged, often a dead SSD (you're screwed).If it is shorted, replace the Piccolo chip (inject 1.3 V on these inductors usually won't give you a strong hotspot). Probe inductors near the Piccolo chip.Troubleshoot Piccolo circuit, it's very sensitive to any sort of water damage in it's vicinity.Same issue but bad probe point that can look good at a cursory investigation. Example of broken trace: (fixed by running wire to replace the broken trace).Inspect the area near R9350, including the trace coming out of Terminal 1 of R9350, oftentimes the neighboring via breaks up the trace, Measure the resistor, it is often out of spec. R9350 PICCOLO_IUVD no longer soldered to board and missing pad for pin 1 (PPVIN_2V7NAND_LB).
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