MacBook A1706 Soldered SSD Not Detected: Liquid Damage Repair
A MacBook A1706 boots to a question mark folder after a liquid spill. The SSD is soldered to the logic board and physically fine; the problem is a corroded resistor on the SSD power delivery circuit. This video walks through finding and replacing it.
Finding the Fault
The question mark folder means the Mac's firmware boots fine but cannot find storage. With soldered SSDs, the storage can't be swapped out; something on the logic board is preventing the Mac from talking to it. The customer reported a liquid spill, which narrows the search to corrosion on the SSD power delivery circuit.
Visual inspection of the SSD area revealed multiple corroded components: capacitors on the PP1V8 and PP3V3 rails, a corroded resistor on the NAND power line, and resistor R9350. Multimeter testing confirmed R9350 as the critical failure. It should read 1.3 megohms; it read open line (infinite resistance). The corroded resistor fell off the board when the multimeter probe touched it.
Why One Resistor Kills SSD Detection
R9350 is a pull-up resistor on the IUVD pin of the U9330 (Piccolo) power management chip. It holds the SSD presence-detection signal at a defined voltage. When the resistor corrodes and goes open circuit, the signal line floats. The Mac's firmware reads an undefined voltage, assumes no SSD is present, and skips straight to the question mark folder.
Replace the resistor, and the signal pulls high again. The Mac detects the SSD. Boot proceeds. In this case, the NAND storage itself was undamaged; only the macOS installation was corrupted by the liquid exposure, so a clean reinstall restored full functionality with data intact.
Question Mark Folder After a Spill?
The SSD itself is almost always intact. If your MacBook got wet and now shows a question mark folder, the circuit between the logic board and the NAND is disrupted by corrosion, not the storage itself. Send it in and we'll identify which component failed.