Pioneer VSX-94TXH Service Manual page 36

1
QQ Step 8: 2nd DSP
3 7 63 1515 0
m
A
RESET
CN402 (Pin 3)
No
Is the logic
of RST_2 "H"
?
Yes
AB
IC201 (Pin 47)
No
Is the logic
of RST_2 "H"
B ?
Yes
Is the logic
of RST_2 maintained
at "H"? (Does it fall to become
"L" periodically?)
Yes
n
CN402 (Pin 2)
SS_2
C
Does the logic
No
of RST_2 periodically
become "H" or
"L"?
Yes
AC
TE
L 13942296513
IC201 (Pin 37)
Does the logic
No
of RST_2 periodically
become "H" or
"L"?
D
Yes
j
SPICLK
CN401 (Pin 16)
Is the clock
No
signal output while the
voltage at SS_2
is "L"?
Yes
AD
IC201 (Pin 36)
E
Is the clock
No
signal output while the
voltage at SS_2
is "L"?
Yes
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F
36
1
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2
Check the output from the
DIGITAL MOTHER Assy.
Check the resistors and patterns
in the path.
The 2nd DSP or the commu-
No
nication path is in failure.
Check the output from the
DIGITAL MOTHER Assy.
Check the resistors and patterns
in the path.
Check the output from the
DIGITAL MOTHER Assy.
Check the resistors and patterns
in the path.
x ao
y
. i
2
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3
8
k
CN401 (Pin 19)
Is the clock
signal output while the
voltage at SS_2
is "L"?
Yes
AE
IC201 (Pin 34)
Is the clock
signal output while the
voltage at SS_2
is "L"?
Yes
AF
IC201 (Pin 35)
Is the clock
signal output while the
voltage at SS_2
is "L"?
Yes
i
CN401 (Pin 18)
Is the clock
Q Q
3 6 7
signal output while the
voltage at SS_2
is "L"?
Yes
It is very difficult to diagnose
which part is in failure.
u163
VSX-94TXH
3
4
2 9 9 4
For the following diagnosis, a digital
oscilloscope must be used.
MOSI
No
Check the output from the
DIGITAL MOTHER Assy.
No
Check the resistors and patterns
in the path.
MISO
No
The 2nd DSP is in failure.
Replace it.
No
Check the resistors and patterns
1 3 1 5 0 5 8 2 9
in the path.
m
co
.
4
2 8
9 9
9 4 2 8 9 9