4. TROUBLE SHOOTING
- 64 -
Copyright © 2012 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
82n
L801
C813
n0
1
1u
C807
n0
1
C814
4.7u
C806
C805
4.7u
n0
1
C815
VREG_MSME_1.8V
C810
10n
U800
3
4
3
5
3
0
3
7
1
0
2
2
5
6
2
7
2
5
2
5
4
5
15
12
13
19
32
21
55
50
37
54
10
4
14
24
31
57
40
47
36
53
42
58
51
56
46
49
43
29
28
33
6
1
1
1
7
2
8
1
9
8
2
2
6
1
4
4
9
3
8
3
8
4
3
2
1
4
2
D
N
G
3
D
N
G
1
M
F
_
D
N
G
A
2
M
F
_
D
N
G
A
3
M
F
_
D
N
G
A
4
M
F
_
D
N
G
A
4
D
N
G
M
F
_
D
N
G
A
1
T
B
_
D
N
G
A
2
T
B
_
D
N
G
A
3
T
B
_
D
N
G
A
4
T
B
_
D
N
G
A
5
T
B
_
D
N
G
A
6
T
B
_
D
N
G
A
7
T
B
_
D
N
G
A
GND1
SYS_RST_N
I2C_SDA
I2C_SCL
FM_HRX_IN
FM_PRXTX_IO
FM_I2S_SD
FM_I2S_WS
FM_I2S_SCK
BT_PCM_IN
BT_PCM_CLK
SLEEP_CLK
BT_UART_RXD
BT_UART_TXD
BT_UART_CTS
BT_UART_RTS
VDD_IO
VDD_XO_BIAS
VREG_DIG
VREG_ANA
VDD_LDO_IN
VDD_FM_1P3_1
VDD_FM_1P3_2
VDD_FM_1P3_3
VDD_FM_1P3_4
VDD_DIG_1P3
VDD_FM_DAC
VDD_BT_PA
VDD_BT_1P3_1
VDD_BT_1P3_2
VDD_BT_1P3_3
VDD_BT_1P3_4
T
N
I
_
S
D
R
_
M
F
K
L
C
_
S
Y
S
L
_
O
L
_
M
F
R
_
O
L
_
M
F
T
U
O
_
M
C
P
_
T
B
C
N
Y
S
_
M
C
P
_
T
B
Q
E
R
_
K
L
C
_
T
B
E
V
I
T
C
A
_
T
B
S
U
T
A
T
S
_
T
B
M
R
I
F
N
O
C
_
X
T
O
I
F
R
_
T
B
00
8
R
M1
L802
82n
47p
C804
C808
10n
L800
68n
10n
C811
0.1u
C812
+3V_WLAN_WCN
p0
1
C809
R806
1M
VREG_MSME_1.8V
I
N
D
20
8
R
C803
22p
I
N
D
10
8
R
C
N
Y
S
_
M
C
P
_
T
B
BT_PCM_SYNC
BT_PCM_CLK
BT_PCM_CLK
SLEEP_CLK
L
_
M
F
R
_
M
F
NFC_WCN_HWI2C_SCL
FM_ANT
BT_UART_CTS
BT_UART_RTS
E
V
I
T
C
A
_
T
B
Y
T
I
R
O
I
R
P
_
T
B
E
V
I
T
C
A
_
N
A
L
W
T
C
Q
_
F
R
_
T
B
N
C
W
_
K
L
C
_
M
F
_
T
B
N
C
W
_
Q
E
R
_
K
L
C
_
M
F
_
T
B
T
N
I
_
S
D
R
_
M
F
BT_UART_TX
BT_UART_RX
BT_RST_N
N
I
_
M
C
P
_
T
B
BT_PCM_OUT
BT_PCM_OUT
NFC_WCN_HWI2C_SDA
3
1
n
i
p
o
t
e
s
o
l
c
7
3
n
i
p
o
t
e
s
o
l
c
BT/FM Module : WCN2243
4
5
n
i
p
o
t
e
s
o
l
c
5
n
i
p
o
t
e
s
o
l
c
+1V2_MSM_A2_WCN
U802
77
85
64
58
30
43
40
42
55
57
69
68
59
50
83
65
44
61
73
72
60
34
52
86
47
37
32
24
70
10
1
7
3
79
49
62
76
54
67
81
66
51
78
74
35
4
2
8
38
36
5
48
46
31
VDD_CORE1
VDD_CORE2
VDD_CORE3
VDD_CORE_AON1
VDD_CORE_AON2
VDD_CORE_AON3
VDD_IO
VDD_FEM
VDD_SDIO
VDD_RFA1
VDD_RFA2
VDD_PA
VDD_TCXO
VDD_RFA3
VDD_RFA4
VDD_RFA5
VDD_RFA6
VDD_RFA7
VDD_RFA8
VDD_RFA9
GND_A21
GND_D1
GND_D2
GND_D3
GND_D4
GND_A2
GND_D5
GND_D6
GND_D7
GND_D8
GND_A3
GND_A4
GND_D9
GND_A5
GND_A6
GND_A7
GND_A8
GND_A9
GND_A10
GND_A11
GND_A12
GND_A13
GND_A14
GND_A15
GND_A16
GND_A17
GND_A18
GND_A19
GND_A20
GND_A1
GND_A22
GND_A23
VDD_RFA10
VDD_RFA11
C850
0.1u
0.1u
C829
+1V3_MSM_A3_WCN
C835
220n
100p
C847
C833
100p
22u
C845
100p
C848
C851
100p
C836
100n
FB801
60
VREG_MSME_1.8V
C846
10n
C827
4.7u
C849
2.2u
C844
10n
+1V8_WLAN_TCXO
10n
C824
+1V2_WLAN_WCN
C834
2.2u
C828
0.1u
FB800
?
+3V_WLAN_WCN
close to pin78
TP2
TP1
TP3
TP1