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LGE Internal Use Only
Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
4. TROUBLE SHOOTING
Fig4-28. SW & FEM placement
Fig4-29. SW & FEM schematic
CHECKING FLOW
Mobile SW
(Unplug RF cable)
Yes
No
No
Yes
Replace SW400
Check U401
Mobile S/W, FEM
is ok
Check SW400
between TP1 and TP2
Is short
FEM
(Plug RF cable)
Check Control Signal
TP3, TP4 is ok
TP3
TP4
TP1
TP2
SW400
U401
FL400
4.2.2.1 Mobile Switch & FEM Circuit
E
1
0
0
-
9
6
3
0
2
1
0
4
W
S
T
N
A
1
G
2
G
3
G
p
3
3
6
1
4
C
I
N
D
2
2
4
C
4
2
4
C
p
5
1
3
B
R
0
0
6
2
-
0
3
4
8
M
M
0
0
4
W
S
GND1
3
GND2
4
5
GND3
6
GND4
IN
1
2
OUT
5
1
4
C
p
0
0
1
1
2
4
C
I
N
D
3
2
4
C
p
6
5
2
2
9
D
N
G
3
2
5
1
T
U
O
_
X
R
0
0
8
1
M
S
G
6
2
T
U
O
_
X
R
0
0
8
1
M
S
G
X
T
_
0
0
9
1
_
0
0
8
1
M
S
G
5
1
1
T
U
O
_
X
R
0
0
9
1
M
S
G
7
8
2
T
U
O
_
X
R
0
0
9
1
M
S
G
1
1
T
U
O
_
X
R
0
5
8
M
S
G
2
2
T
U
O
_
X
R
0
5
8
M
S
G
X
T
_
0
0
9
_
0
5
8
M
S
G
7
1
1
T
U
O
_
X
R
0
0
9
M
S
G
3
4
2
T
U
O
_
X
R
0
0
9
M
S
G
C
N
1
2
9
1
1
C
V
2
C
V
0
2
0
0
4
L
F
B
F
5
8
0
C
-
S
H
S
L
1
1
T
N
A
1
D
N
G
9
4
2
0
1
D
N
G
2
D
N
G
0
1
2
1
3
D
N
G
4
D
N
G
3
1
5
D
N
G
4
1
6
D
N
G
6
1
8
1
7
D
N
G
8
D
N
G
T
P
1
T
P2
T
P3
T
P4