19
VSX-518-K
5
6
7
8
5
6
7
8
A
B
C
D
E
F
5. DIAGNOSIS
5.1 DIAGNOSIS FLOWCHART (DSP ASSY)
•
W
hen a sound is not out in the multi-CH signal playback mode or surround mode with the digital signal input.
(SurroundBack is not output by setting.)
• Suppose CR to be normal contact and that is not damaged.
• This shows failure analysis of DSP Assy.
Step 4: 3 V to 5 V conversion
Step 2: BtoB connector
Step 1: MUTE pin
C
N
901, C
N
701, C
N
951
Are the
connectors securely
inserted?
Turn the power off and
insert the connectors
securely.
N
o
IC952 (pin 1
8
)
Do
convert 3
V
into
5
V
for pin 2
input?
Replace IC
8
01.
Replace IC901.
Replace IC902.
A
Yes
To Step 3
To Step 2
To Step 4
Step 0: Preliminary confirmation
Confirm the following items before checking
Do screws
of COAX Jack
securely tighten
?
Tighten screws securely.
N
o
Yes
To Step 1
IC
8
01 (pin 54)
Is the
voltage of output
signal 0
V
?
N
o
Replace IC952.
N
o
Yes
MUTE
Troubleshooting for all destination
Step 3: Regulator IC
Check the C
N
901 and
REGULATOR assy.
IC901 (pin 4)
Is the
voltage of around
5
V
to 5.3
V
input?
N
o
Yes
(to chassis)
IC902 (pin 5)
Is the
voltage of 1.25
V
output?
N
o
(to chassis)
IC901 (pin 5)
Is the
voltage of 3.3
V
output?
N
o
Yes
Yes
Yes
IC952 (pin 17)
Do
convert 3
V
into
5
V
for pin 3
input?
Replace IC952.
N
o
Yes
IC952 (pin 16)
Do
convert 3
V
into
5
V
for pin 4
input?
Replace IC952.
N
o
Yes
IC952 (pin 15)
Do
convert 3
V
into
5
V
for pin 5
input?
Replace IC952.
N
o
Yes
(to chassis)
Part shape and Pin arrangement
of IC901 and IC902
