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.
Standard Repair Process Detail Technical Manual
Voltage and speaker checking method
when there is no audio
C. Audio error_No audio/Normal video
A21
Established
date
Revised
date
Error
symptom
Content
A21
①
②
③
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
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Summary of Contents for 75SJ857A
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