LG 75SJ857A Service Manual page 56

Standard Repair Process Detail Technical Manual
symptom
Content
Checking order when there is no audio
1.Check the contact condition of or 13.2V connector of Main Board
2. Measure the 13.2V input voltage supplied from Power Board
(If there is no input voltage, remove and check the connector)
3.Connect the tester RX1 to the speaker terminal and if you hear the Chik Chik sound when you touch the
GND and output terminal, the speaker is normal.
Error
C. Audio error_No audio/Normal video
Voltage and speaker checking method
when there is no audio
②
Established
Revised
1 SPK_R-FT 7 SPK_L-_TW
2 SPK_R+FT 8 SPK_L+_TW
3 SPK_L-FT 9 SPK_R-_CT
4 SPK_L+FT 10 SPK_R+_CT
5 SPK_R-_TW 11 SPK_L-_CT
6 SPK_R+_TW 12 SPK_L+_CT
A21
date
date
③
①
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A21