LG W4-4 - Power Supply on Main Board

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ELECTRICAL TROUBLESHOOTING GUIDE
No 3.3 VA (3.3VA_MICOM)
Is D101 diode input
supply 3.8 VA?
Check 3.8 VA on MAIN board.
YES
YES
NO
Check D101 and replace.
No 3.3 V
Is the
VCC supplied to IC155
pin3?
Check 3.8 VA on SMPS board.
YES
YES
NO
Is there
signal at IC155
pin2?
Check IC100 pin58 (DCDC33_CTRL).
Check IC155 and replace.
YES
NO
3. POWER SUPPLY ON MAIN BOARD