No audio
Screen normal
Off
N
Y
Cancel OFF
Check audio B+
24V of Power
Board
Normal
voltage
Y
N
Replace Power Board and repair parts
Check
Speaker
disconnection
N
Y
Replace Speaker
Replace MAIN Board
End
C. Audio error
No audio/ Normal video
☞
A20
☞
A21+A18
Disconnection
Established
date
Revised date
8/16
Standard Repair Process
8
Error
symptom
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Summary of Contents for 49UF77 Series
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