3-20
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Audio out abnormal
Check Audio jack & mode
YES
YES
Check U504
YES
Check signals from MPEG
YES
Replace IC(U504)
MAIN ELECTRICAL TROUBLESHOOTING GUIDE
Audio in/speaker
abnormal
Replace IC(U502)
Replace
Q510 and Q519
Check Audio jack &
mode S/W
NO
YES
YES
Is Q510
and Q519 OK.
Speakers
NO
YES
YES
Is speakers OK.
Replace
B. AUDIO OUT ABNORMAL
D. AUDIO IN/SPEAKER ABNORMAL
Video in abnormal
Refer to LCD part
Replace
(U501 IC)
Check Video jack
& mode
NO
YES
YES
Is U501 OK.
Check
U701 Pin 14
YES
YES
E. VIDEO IN ABNORMAL
Video out abnormal
Check Video jack & mode
YES
YES
Check Video signals from MPEG
YES
Check IC(U501)
YES
Check LC filter
C. VIDEO OUT ABNORMAL