Power Supply On Main Board - LG LAB550H Service Manual

ELECTRICAL TROUBLESHOOTING GUIDE

2. POWER SUPPLY ON MAIN BOARD

No 3.3 V, 3.3V_MTK
Is the
VCC supplied to IC157
pin1?
Is there
signal at IC157
pin3?
Check IC157 and replace.
No Analog_3.3V
Is the
VCC supplied to IC706
pin1?
Is there
signal at IC706
pin3?
Check IC706 and replace.
No 3.3 VA
Is the
VCC supplied to IC152
pin3?
Check IC152 and replace.
YES
YES
YES
YES
YES
YES
YES
YES
NO
NO
Check IC101 pin24 (P_CTRL1).
NO
NO
Check IC101 pin24 (P_CTRL1).
NO
2-42
Check 3.3 VA.
Check 5 VA.
Check 12 VA.