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DVD has no sound output
Check
whether pin 8 12V
power supply of U117
is normal
Check +A12V power
supply circuit
Check
whether pin 2/6
signal of U117 is
normal
Change MT1389
Check
whether mute circuit is
normal
Check mute circuit
4. Troubleshooting process for “DVD has no sound output” is shown in the figure 3.3.2.4:
Trouble description: when machine switches in DVD state, disc read is normal, image is normal, no
sound output and external sound input is normal.
Figure 3.3.2.4 Troubleshooting flow chart for “DVD has no sound output”
Y
N
N
N
N
Y
Y
Y
Check
whether pin 1/7
audio output of U117 is
normal
Change U117
Check
whether pin 3/13
audio output of U107 is
normal
N
Check U107
Y
N
Check
whether pin 23/24
signal input of STV8216_23
is normal
Check line between
STV8216 and U107
Y
Change STV8216
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