Pioneer SC-LX72, Service Manual

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SC-LX82
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A
B
C
D
E
F
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5. DIAGNOSIS
5.1 DIAGNOSIS FLOWCHART
(1) Simplified diagnosis
Errors in the DSP Block of the DSP Assy (those simply and roughly predictable by machine operation only)
• Has DSP block caused the malfunction?
Inputting a 2 ch PCM (such as CD) digital signal, check if the sound plays by switching AUTO SURR / STREAM DIRECT.
When the sound doesn’t play in AUTO SURROUND or DIRECT MODE though it does in PURE DIRECT (PCM DIRECT)
MODE, DSP block might be defective.
(2) Troubleshooting
• Assume that the LCRs are neither in poor connection nor damaged.
• This shows failure analysis for the DSP Block of the DSP Assy.
Step 2: Power supply Step 1: Connections
CN2001,CN2002,CN2003,
CN2602,CN2901,CN2902
Are the
connectors securely
inserted?
Insert the connectors
securely.
No
CN2003 (Pins 1-3)
IC2307 (Pin 2)
Is the voltage
6 V?
No
6V input
Connection with
the INTERFACE Assy.
1st, 2nd Block 3.3V
CN2601
Connection with
the DIGITAL MAIN Assy.
No
Replace CN2003.
Check the output from the
REG Assy.
Yes
Replace IC2307.
Yes
Is there
any poor connection
at Pins 1-3 of
CN2003?
Is the voltage
4.2 V-4.5 V
?
No
No
The output and GND may be short-
circuited. Check the path between
them.
Yes
Yes
Is IC2307
abnormally hot?
A
Yes
Is the
FFC securely
inserted?
Insert the FFC
securely.
No
CN2201
Connection with
the DIGITAL_BRIDGE Assy.
Yes
Is the
connector securely
inserted?
Insert the connector
securely.
No
Yes
To Step 2
A
• The parts marked like in the following chart are located in "Check Points of the DSP Assy." A
B
IC2301 (Pin 72, etc.) 1st DSP 3.3V
Is the voltage
3.3 V?
No
Yes
C
Check the parts and patterns
in the path.
Check the parts and patterns
in the path.
Check the parts and patterns
in the path.
IC2307 (Pin 4)
Is the voltage
3.3 V?
No
Yes
IC2304 (Pin 20)
LATCH 1
Is the voltage
3.3 V?
No
Yes
D
E
[1] DSP Troubleshooting