Read LG 42LD550 (CHASSIS:LA02B) Service Manual online
10. Analog TV Audio
Check RF Cable & Signal
Follow procedure
‘8. All source audio’
trouble shooting guide.
ok
Check Tuner 3.3V Power
L701
Replace L701
Check Tuner 1.2V Power
IC700 2 pin : 1.2V
Check CVBS Signal
TU700 11 Pin
Replace IC700.
ok
ok
ok
No
No
No
Bad Tuner. Replace Tuner.
Check Tuner 5V Power
L700
ok
Check IC8003
No
Replace IC8003
No
Replace L8007
ok
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