Read LG 42LD550 (CHASSIS:LA02B) Service Manual online
8. All Source Audio
Check the TV Speaker Menu
(Menu -> Sound -> TV Speaker)
On
ok
ok
Check Output Signal P8800
1, 2, 3, 4 pin.
Replace Audio AMP IC(IC8801)
ok
No
Check Connector & P8800
Replace connector
if found to be damaged.
if found to be damaged.
ok
No
Check speaker resistance
and connector damage.
Replace speaker.
ok
No
Off
Toggle the Menu
Check AMP IC(IC8801) Power
*20V, 3.3V, 1.8V.
No
Check Regulator IC8800
Check Mstar I2S Output
R8801, R8802, R8803
No
Check signal line. Or replace BCM( IC900)
Check AUDIO_MASTER_CLK
R8828
No
Replace BCM( IC900) or Main Board.
ok
Check AMP I2C Line
R8804, R8805
No
Check signal line. Or replace BCM( IC900)
*20V Voltage is dependent on Model
32/42/46LD550 , 47LD650 => 20V
52/60LD550 , 55LD650 => 24V
32/42/46LD550 , 47LD650 => 20V
52/60LD550 , 55LD650 => 24V
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