55
SC-LX81
5
6
7
8
5
6
7
8
A
B
C
D
E
F
Insert the connectors securely.
C
N8
01, C
N
1701(FFC)
N
o
Yes
Check the parts and patterns in
the path.
C
N
1001 (Pins4-6)
12
V
input
1
N
o
N
o
Yes
Check the DIGITAL
MOTHER Ass'y
Yes
To STEP 2
Are the
connectors
securely
inserted?
Is the
voltage 12
V
?
Step 1:Connectors
Step 2:Power supply
Is there
any loose
connection of
C
N
1001?
IC11 (Pin 2)
3.3
V
Regulator IC input
2
3
N
o
Yes
Is the
voltage 5
V
?
Check the parts and patterns in
the path.
IC
8
01 (Pin 5)
USB Power S
W
4
N
o
Is the
voltage 5
V
?
Check the patterns in the path.
IC31 (Pin 2)
N
o
Yes
Yes
Is the
voltage 5
V
?
Check the
parts and
patterns in the path.
IC921 (Pin 14)
N
o
Yes
Is the
voltage 5
V
?
Check the parts and patterns in
the path.
Check the parts and patterns in
the path.
IC701 (Pins 3,16,32,43,55,61,7
8
,
8
9,103,
113,125,136,151,15
8
,176,192,201)
N
ET
W
ORK Media
processor IC
9
N
o
Yes
Is the
voltage 3.3
V
?
IC
8
61 (Pins 14, 36, 4
8
)
N
o
Yes
Is the
voltage 3.3
V
?
Check the parts and patterns in
the path.
IC791 (Pin 1, 40)
N
o
Yes
Is the
voltage 3.3
V
?
Check the parts and patterns in
the path.
IC
88
1 (Pins 37,47)
FLASH ROM
6
N
o
Yes
Is the
voltage 3.3
V
?
Check the parts and patterns in
the path.
IC
8
91 (Pins 1,3,9,14,27,43)
SDRAM
7
N
o
Yes
Yes
Is the
voltage 3.3
V
?
Check the parts and patterns in
the path.
IC911 (Pin 14)
5-3 Converter
8
N
o
Is the
voltage 3.3
V
?
To STEP 1
IC11 (Pin 4), IC21 (Pin 2)
3.3
V
Reg. output/1.
8V
Reg. input
5
N
o
N
o
Yes
Replace IC11.
Yes
Is the
voltage 3.3
V
?
Is IC11
abnormally
hot?
The output and G
N
D may be
short-circuited. Check the path
between them.
A
IC21 (Pin 4)
1.
8V
Regulator output
10
11
12
N
o
Yes
Is the
voltage 1.
8V
?
N
o
Replace IC21.
Yes
Is IC21
abnormally
hot?
The output and G
N
D may be
short-circuited. Check the path
between them.
3) Network block troubleshooting
3-5 Converter
iPod Co-Processor