Power Supply On Main Board - LG XV-BD212 Service Manual

ELECTRICAL TROUBLESHOOTING GUIDE

2. POWER SUPPLY ON MAIN BOARD

No 3.3 V
YES
Is the
Vcc 3.8 VA supplied to IC152/
IC153 pin2?
YES
Is there
'H' signal at IC152/ IC153
pin1?
YES
Check IC152/ IC153 and replace.
No 5 V
YES
Is the Vcc
6 VA supplied to IC1A1/ IC154/ IC155/
IC203 pin2?
YES
Is there
'H' signal at IC1A1/ IC154/ IC155/
IC203 pin1?
YES
Check IC1A1/ IC154/ IC155/ IC203
and replace.
NO
Check 3.8 VA on SMPS board.
Check LDO_CTRL/ DCDC33_CTRL line
NO
from IC101(pin58, 68).
NO
Check 6 VA on SMPS board.
Check LDO_CTRL/ DCDC33_CTRL line
NO
from IC101(pin58, 68).
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