Read LG 42LV5400 (CHASSIS:LA12E) Service Manual online
Check RF Cable & Signal
Check Tuner 3.3V Power
L2103
Replace L2103
Check Tuner 1.26V Power
IC2103 2pin : 1.26V
Check IF_P/N Signal
TU2101 17/18 Pin
Replace IC2103.
Check Tuner 5V Power
L2104,2101
Check IC507
Check BCM LVDS Output
Replace or BCM( IC101) or Main Board.
ok
ok
ok
ok
ok
No
No
No
No
No
Replace ICIC507
No
Bad Tuner. Replace Tuner.
Replace L2101/4
ok
2. Trouble shooting - No video (Digital TV video)
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