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Why injecting voltage with CPU installed?
If you have good diode mode reading without CPU, you should try another CPU.
If still low reading without CPU, there is something else bad on that line.
found the problem! masking with uv only pp3v3_s3-mini pins on wifi card, the computer boots fine! but the line is not short! and has a good value (0,630)
You have a low value on 1V5_S0 power rail.
Not too low, corresponding power supply can still work; even with CPU connected.
When you connect the airport card, overcurrent mode is triggered for that power supply.
Small current increased caused by airport card consumption, I suppose.
"pp3v3_S3_min has a low value too (0,067)"
Remove/replace Q3406 and test again.