Read LG 42LV5400 (CHASSIS:LA12E) Service Manual online
3. Trouble shooting - No video (Analog TV video)
Check RF Cable & Signal
Check Tuner 3.3V Power
L2103
Replace L2103
Check Tuner 1.2V Power
IC2103 2 pin : 1.2V
Check CVBS Signal
TU2101 11 Pin
Replace IC2103.
Check Tuner 5V Power
L2104,2101
Check IC507
ok
ok
ok
ok
ok
No
No
No
No
No
Replace IC507
No
Bad Tuner. Replace Tuner.
Replace L2104,2101
ok
Check BCM LVDS Output
Replace BCM( IC101) or Main Board.
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