Read LG 42LV3700-UD (CHASSIS:LA12B) Service Manual online
15. Trouble shooting - No audio (Head phone audio out)
Check Head phone Cable
for damage or open conductor
ok
ok
Check Earphone AMP Mute
(Pin 13)
Check Audio OSD
(Audio OSD active or inactive mode?)
Check R3816 & R3858, JK3803
No(active)
Check Earphone output
(Pin 5, 16)
ok
No
Replace IC3804 TPA6132A2
ok
Follow procedure & refer to Audio signal block
Diagram
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