Diagnosis; Diagnosis Flowchart - Pioneer VSX-1020-K Service Manual

5

5. DIAGNOSIS

5.1 DIAGNOSIS FLOWCHART

Simplified diagnosis
Errors in the Audio Part of the D-MAIN Assy (those simply and roughly predictable by machine operation only)
• Sound abnormality in Delay
If sound abnormality does not occur in the Delay OFF state but occurs in the Delay ON state, it is most likely that a failure
has occurred in SDRAM (IC251) or LATCH (IC281, IC291) in the DSP Part.
• No sound at analog signal input
If sound abnormality does not occur with digital signal input (COAX, OPT, etc.) but occurs only with analog signal input,
it is most likely that a failure has occurred in the AD converter (IC501).
• No sound with the PQLS ON (normal sound with the PQLS OFF)
If no sound is output during CD playback with the PQLS ON, it is most likely that a failure has occurred in the crystal
oscillator (X361). (Diagnosis point A)
DSP Troubleshooting
<If no sound is output in Multi-Channel-Signal Playback or Surround mode with the COAX, OPT, USB, and HDMI inputs>
• Assume that the LCRs are neither in poor connection nor damaged.
• Assume that diagnosis is performed from Side A.
• This shows failure analysis for the DSP Part of the D-MAIN Assy.
1
• The parts marked like in the following chart are located in "Check Points of the D-MAIN Assy."
Step 0: Preliminary confirmation
Confirm the following items before checking
Do
screws of
earth terminal (KN481)
securely tighten
?
Yes
To Step 1
Step 1: MUTE pin
IC301 (Pin 84) (or R324)
DSP1MUTE
Is the
No
voltage of output
signal 0 V
?
1
Yes
To Step 2
Step 2: Power supply
V+5_DDD1
IC581 (Pin 1)
(to chassis)
Is the
No
voltage of around
5 V input?
2
Yes
V+3R3_D
IC581 (Pin 3)
(to chassis)
Is the
No
voltage of 3.3 V
output?
3
Yes
5
6
No
Tighten screws securely.
Note:
If this section is not fixed,
the GND for DSP module
may lifted from the chassis
and cause instable potential
and lead to product failures.
Check the DSP and down
stream block. Go to step 6.
No
Replace IC301.
Check the Q1900 and
its periphery block.
Check the C121, C114,
C509 and C459.
NG
Replace IC581.
6
7
D582 (Cathode)
Is the
voltage of around
2.7 V output
?
4
Yes
C333 (+ side)
Is the
voltage of 1 V
input?
5
Yes
C506 (+ side)
Is the
voltage of 5 V
input?
6
Yes
C552 (+ side)
Is the
voltage of around
5 V input?
7
Yes
C606 (+ side)
Is the
voltage of 5 V
input?
8
Yes
To Step 3
VSX-1020-K
7
8
No
Replace D582.
V+1_DSPF
No
Check the C333.
NG
Replace IC582 (side B).
V+5_DAC
No
Check the C506 and C527.
NG
Check the MAIN Assy.
V+5_DACD
No
Check the C552.
NG
Replace R552.
V+5_DACA
No
Check the C606, C656, C706
and C756.
NG
Replace Q551 (side B).
8
A
B
C
D
E
F
25