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Not sure why the change, but after sitting down today to test the board, I currently am missing pp5v_s4rs3... (well I should say it is power cycling). If I am not mistaken, this signal comes from the charging port, so I replaced with a known-good charging board but still same issue. Do not measure a short on that line. Not sure what to do from here, but not getting the same results as yesterday and am stuck again. Thanks again for the help.
Test the board alone on the desk, without LIO flex connected; keep only 5 pins DC cable connected.
5V_S4 comes from L7520.
PPBUS_G3H and 3V42_G3H both stable?
Also check 3V3_S5/SUS.