BBK DK1410SI - Page 59

No sound for external input
All external outputs
have no sound
OK
Check power
supply circuit
Change CD4052
No sound for tuning
OK
1. Whether pin 20 of XS207 is
high level (3.3V)
2. Whether V5 and V6 are normal
3. Check other peripherical
circuit of TV6
Check clock circuit in the
position of Y2
No sound for external mixed
left and right channels
Y
N
Y
Check the path between N7
(CS5340) and N5 (CD4052)
Change M2 (TAS5508)
and check other circuit
Whether power
supply of N5 (CD4052),
N7 (CS5340) N4
(7AHCT125)
is normal
Use
oscillograph to
check whether pin 3, 13
of N5 (CD4052) have
waveform signal
output
N
Y
Check
whether pin
10, 12 of N7 (CS5340)
have waveform
signal input
N
Y
Change N7
(CS5340) and check
whether it is
normal
N
Change N4
(THHCT125) and check
whether it is
normal
OK
Y
Change tuner
and check whether it
is normal
OK
Change N5
(CD4052) and check
whether it
is normal
Check whether
pin 7 and 14 of N6
(SAA6558) are
about 5V
Whether clock
in the place of crystal
oscillator Y2
is 4.3V
Change SAA6558
N
Y
Y
N
N
N
Y
N
Check the path between
left/right channel input
terminal and XS401
Whether pin 7
and 8 of XS401
have signal
Y
Y
N
Check power
supply circuit
OK
Change N4 (74ACT125)
Change N12 (TAS5508)
Change N5
(CD4052) and check
whether it is
normal
Check whether
power supply of N4
(74ACT125) is
normal
Y
N
N
18. Trouble shooting for no sound of external input is shown as the following figure 3.3.2.19:
Figure 3.3.2.19 Troubleshooting flow chart for no sound of external input
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