Sanyo DC-DVD888 Service Manual page 30

TROUBLE SHOOTING
(This is a basic trouble shooting.)
AUDIO PART
1. When time display OK and sound NG
or When S/PDIF OK and analogue NG.
Check DAC output
(IC131 pin11/14).
NG
Check (BCLK/
ASDATA/LRCLCIC131
pin 16/17/18).
NG
Check IC127
pin 105/106/107.
NG
Check IC127 peripheral.
(IC127 NG)
2. When time display NG and sound NG.
Exchange DVD:roader.
NG
Check IC127 peripheral.
(IC128 NG)
Check CD:CN810 pin2/3/4.
NG
Exchange loader.
NG
Exchange MPEG
p.w.board.
Tracking signal of
after DAC output.
OK
Check MUTE signal.
Check IC131 pin1(27MHz)
and pin2(384FS).
Check IC131 power source
and peripheral circuit.
OK
Check IC131 RESET/
control signal(pin6/7/8/9).
Check BCLK/ASDATA/
LRCLK signal line.
Check IC127 and
OK
its peripheral.(IC127 NG)
Loader NG.
OK
Check IC127 peripheral.
(IC127 NG)
OK
Loader NG.
OK
3. When S/PDIF NG and analogue OK.
Check optical module
and signal line.
NG
Check signal line
peripheralpattern
and parts.
4. When S/PDIF NG and analogue NG.
Check time display.
NG
Check check 2
5. When pop noise (when usual operate.)
Check same output as
SPDIF and RCA.
NO
Check pop noise only
RCA output.
NO
IC127 (MPEG) NG.
6. When pop noise (Power ON/OFF).
Check MUTE circuit.
(Normality ?)
NO
Check MUTE circuit.
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Check IC127 peripheral.
(IC127 NG)
OK
Check check 1
OK
Loader NG
YES
Muting circuit trouble.
Check MUTE signal.
YES
Specity place of noise
generation.
Check timing with MUTE
YES
signal and its peripheral.