ELECTRICAL TROUBLESHOOTING GUIDE
2. POWER SUPPLY ON MAIN BOARD
No 5.1 VA
Is the VCC
12 VA supplied to IC201
pin1?
Check IC201 and replace.
No 3.3VA_MICOM
Is the VCC
12 VA supplied to IC202
pin1?
Check IC202 and replace.
No 1.8VA_STB
Is the VCC
5.1 VA supplied to IC204
pin1?
Is there any voltage
on IC204 pin5?
Check IC204 and replace.
YES
YES
YES
YES
YES
YES
YES
NO
Check 12 VA on SMPS board.
NO
Check 12 VA on SMPS board.
NO
NO
Check PWR_CTL or voltage on IC302 (Micom).
3-44
Copyright © 2020 LG Electronics Inc. All rights reserved.
Refer to No 5.1 VA.
Only for training and service purposes.