LENOVO G550S LA-9901P NO VCORE PROBLEM (SOLVED)
Test Admin (18 Mar 2025)

PSU SHOWING 0.24AMP
3.3V AND 5V ALW PRESENT
OTHER VOLTAGES MEASURED:
1.04V PL701
0.88V. PL601
1.5V. PL501
2.62V PL302
1.5V VDDQ
DURING VOLTAGE TEST FOUND PU901 (NCP6132A) PIN4 VRON 3V PRESENT BUT PIN1 VCC 3.6V ONLY INSTEED OF 5V
BECAUSE U38 5VALW TO 5VS SWITCH SOURCE TRANSFER 3.6V ONLY,
SVID CLOCK PULSE SEEN AS SHOWN BELOW WF
U38 GATE 15.2V ok but OUTPUT not Transferred properly
SO Replaced U38 N-CH MOSFET
all ok, booting tested by USB init.
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