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Flow Chart of Troubleshooting
10-2
PM IC
VREG_RFRX400
C423
C420
R411
C426
C400
V_RF_S3_2.7V
VBATT
R403
C417
VBATT
C411
C401
R430
C421
OSC400
C429
R409
C414
C410
R407
TP400
C434
C415
Q400
1
3
2
USB_5V
VREG_TCXO_2.8V
C418
C428
C403
C427
3
1
2
V_RF_S3_2.7V
U401
EXT_5V
C412
VREG_RFUBM
C424
C433
VREG_MSMC_1.2V
C430
C404
L400
R404
R408
VREG_MSMP_2.6V
R405
VREG_BT_2.6V
V_RF_S2_2.1V
C413
VREG_MSMA_2.6V
V_MMC_2.85V
L402
C425
VDD_EAR_2.9V
VREG_MSMP_2.6V
C419
R401
C416
C407
R412
VREG_MSME_1.8V
L401
VREG_RFRX2_2.85V
C422
C402
R410
L6
VREG_S3
7
L
3
2
S
_
D
D
V
L8
VREG_S2
L9
VREG_MMC
K9
SLEEP_CLK
L1
MPP4|LCD_DRV_N
L10
VREG_RUIM
L11
XTAL_IN
L2
MPP3|KPD_DRV_N
L3
VIB_DRV_N
L4
KPD_PWR_N
5
L
C
M
S
M
_
D
D
V
K11
XTAL_OUT
K2
MPP7|CBLPWR_N
K3
AMUX_OUT
K4
VREG_MSMC
K5
VSW_MSMC
K6
VSW_S3
K7
VSW_S2
K8
VREG_MSME
H7
MPP6|RUIM_RST
H8
OPT_2
J1
USB_D_M
J10
VCOIN
J11
VREG_MSMP
J2
USB_D_P
K1
HSET_BIAS
01
K
MI
U
R
_
D
D
V
G8
SBDT|SSBI
H1
USB_VBUS
H10
TCXO_OUT_1
11
H
M
S
M
_
D
D
V
H2
USB_ID
H4
USB_SE0
H5
MPP12|RUIM_IO
H6
MPP10|RUIM_CLK
1
G
V
5_
G
E
R
V
G10
PON_RESET_N
G11
VREG_MSMA
G2
VREG_USB
G4
USB_DAT
5
G
D
N
G
6
G
D
N
G
7
G
D
N
G
F10
PS_HOLD
F11
TCXO_OUT_RF
F2
USB_OVP_G
F4
USB_OE_N
5
F
D
N
G
6
F
D
N
G
7
F
D
N
G
F8
SBCK
E11
TCXO_IN
E2
BAT_FET_N
E4
TCXO_EN_2
5
E
D
N
G
6
E
D
N
G
7
E
D
N
G
E8
SBST
1
F
V
5_
W
S
V
D2
ISNS_P
D4
OPT_1
D5
MPP11|RUIM_M_IO
D6
MPP9|RUIM_M_CLK
D7
MPP5|RUIM_M_RST
D8
TCXO_EN_1
1
E
T
A
B
V
E10
REF_GND
9
B
F
R_
D
D
V
C1
VCHG
C10
MSM_INT_N
C11
REF_BYP
C2
CHG_CTL_N
D1
ISNS_M
D10
REF_ISET
11
D
C
N
D
B11
VREG_WLAN
2
B
NI
A
M
_
D
D
V
3
B
P
G
_
D
D
V
B4
MPP8|REF_OUT
B5
SPKR_IN_M
B6
SPKR_IN_P
B7
MPP2|AMUX_IN2
B8
VREG_RFUBM
4
A
R
K
P
S
_
D
D
V
A5
SPKR_OUT_M
A6
SPKR_OUT_P
A7
MPP1|AMUX_IN1
A8
VREG_RFTX
A9
VREG_RFRX1
B1
VREG_GP3
B10
TCXO_OUT_2
1
C
N
2
C
N
A1
VREG_TCXO
A10
VREG_RFRX2
11
A
N
A
L
W
_
D
D
V
A2
VREG_GP2
A3
VREG_GP1
U400
C409
V_RF_S2_2.1V
BAT400
G
E
N
2
S
O
P
1
TP401
VREG_USIM_3.0V
VDD_WHEEL_3.0V
C405
C431
C406
C408
R406
C432
PMIC_SBST
SIM_RST
MSM_SIM_CLK
SIM_CLK
MSM_SIM_IO
SIM_IO
VF_MSM
BOOT_SW
USB_DAT_MSM
USB_D_M
USB_D_P
USB_OE_MSM
USB_SEO_MSM
TCXO
BUFF_TCXO
JIG_ON_SW
REF_OUT
MSM_SIM_RST
PMIC_SBDT
SLEEP_CLK
ON_SW
PS_HOLD
PON_RESET_N
PM_INT_N
JIG_ON
JIG_ON_SW
TCXO_EN
C336 C337
C
0
4
0
C
0
4
1
C
0
4
2
C
0
4
3
C404
C405
C
0
4
6
C407
C
0
4
8
C409
C410
C
1
4
1
C
1
4
3
C
1
4
4
C415
C
1
4
7
C418
C425
C
2
4
6
C427
C
2
4
9
C
3
4
1
C433
C
3
4
6
L400
L401
L402
OSC400
4
R405 R406
R
0
4
9
R
1
4
0
R
1
4
1
R
1
4
2
0
TP300
U
0
4
0
U
0
4
1
VREG_RFRX400
Summary of Contents for SGH-F400
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