LG UBK80 Service Manual page 64

ELECTRICAL TROUBLESHOOTING GUIDE
POWER SUPPLY ON MAIN BOARD
No 1.5V_DDR
Is the VCC
12 VA supplied to IC206
pin1?
Is there any voltage
on IC206 pin5?
Check IC206 and replace.
No 3.3V_NOR
Is the VCC
3.3 VA supplied to IC209
pin5?
Is there any voltage
on IC209 pin4?
Check IC209 and replace.
YES
YES
YES
YES
YES
YES
NO
Check 12 VA on SMPS board.
NO
Check PWR_CTL4 or voltage on IC302 (Micom).
NO
Refer to No 3.3VA_MICOM.
NO
Check PWR_CTL5 or voltage on IC302 (Micom).
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