VSX-LX70
35
5
6
7
8
5
6
7
8
C
D
F
A
B
E
Step 7: 1st DSP
Check the output from the
DIGITAL MOTHER Assy.
It is likely a boot error.
(It is very difficult to diagnose
which peripheral part of the
DSP is in failure.)
CN401 (Pin 20)
RESET
REQ_1
SPIDS_1
Is the logic
of RST_1
"
H
"
?
No
Yes
Is the logic
of RST_1
"
H
"
?
f
The 1st DSP is in failure.
Replace it.
The 1st DSP is in failure.
Replace it.
R139
w
R134
No
g
CN401 (Pin 21)
g
Is the logic
of RST_1 maintained
at
"
H
"?
(Does it fall to become
"
L
"
periodically
?
)
No
Yes
Yes
Does the logic
become
"
H
"
for a moment
when the input stream
is changed
?
Does the logic
become
"
H
"
for a moment
when the input stream
is changed
?
Does the logic
become
"
L
"
for a moment
when the input stream
is changed
?
Does the logic
become
"
L
"
for a moment
when the input stream
is changed
?
Check the resistors and patterns
in the path.
No
R137
x
Yes
Yes
Check the resistors and patterns
in the path.
No
CN401 (Pin 17)
h
Yes
Check the resistors and patterns
in the path.
No
Yes
Check the output from the
DIGITAL MOTHER Assy.
No
R144
y
Yes
Yes
Check the resistors and patterns
in the path.
No
Check the output from the
DIGITAL MOTHER Assy.
No
Is the clock
signal output while the
voltage at SPIDS_1
is
"
L
"?
Is the clock
signal output while the
voltage at SPIDS_1
is
"
L
"?
Is the clock
signal output while the
voltage at SPIDS_1
is
"
L
"?
Is the clock
signal output while the
voltage at SPIDS_1
is
"
L
"?
Is the clock
signal output while the
voltage at SPIDS_1
is
"
L
"?
Is the clock
signal output while the
voltage at SPIDS_1
is
"
L
"?
CN401 (Pin 16)
SPICLK
j
R146
z
Yes
Yes
Check the resistors and patterns
in the path.
No
Check the output from the
DIGITAL MOTHER Assy.
No
CN401 (Pin 19)
MOSI
k
CN401 (Pin 18)
i
Yes
Yes
Check the resistors and patterns
in the path.
No
No
R142
MISO
AA
It is very difficult to diagnose
which part is in failure.
For the following diagnosis, a digital
oscilloscope must be used.
