Huawei U8350 User manual

U8350 Maintenance Manual Basic Version
V1.0
Prepared by
Product Department
Documentation Team
Date
2011-05-18
Reviewed by
Date
Approved by
Date
Huawei Technologies Co., Ltd.
All rights reserved

U8350 Maintenance Manual Basic Version V1.0
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Revision record
Date
Revision
Version
Revision Cause
Section
Number
Change
Description
Author
2011-05-18
V1.0
Product Department
Documentation Team

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Contents
1 PRODUCT INTRODUCTION................................................................................................................................5
1.1 PRODUCTAPPEARANCE.....................................................................................................................................5
1.2 PRODUCT SPECIFICATIONS................................................................................................................................5
2 MAINTENANCE INFORMATION GUIDE .........................................................................................................7
2.1 DOCUMENT APPLICATION...................................................................................................................................7
2.2 MAINTENANCE PRECAUTIONS...........................................................................................................................7
2.3 OBTAINING MAINTENANCE INFORMATION .......................................................................................................7
3 EXPLOSIVE VIEW OF PRODUCT.....................................................................................................................8
4 LOCATION OF COMPONENTS ON THE MAIN BOARD.........................................................................10
5 SOFTWARE UPGRADE.......................................................................................................................................17
5.1 PREPARATION FOR UPGRADE .........................................................................................................................17
5.2 UPGRADE PROCESS..........................................................................................................................................17
5.3 FORCE DOWNLOAD...........................................................................................................................................19
5.4 CHECK THE FIRMWARE VERSION ...................................................................................................................20
5.5 ERROR HANDLING .............................................................................................................................................20
6 MAINTENANCE TOOLS......................................................................................................................................21
7 DISASSEMBLY PROCEDURE..........................................................................................................................23
8 ASSEMBLY PROCEDURE..................................................................................................................................28
9 TROUBLE SHOOTINGS OF COMMON FAULTS.......................................................................................32
9.1 PRINCIPLE INSTRUCTION..................................................................................................................................32
9.2 NO POWER ON...................................................................................................................................................33
9.2.1 High Current (DC power supply).....................................................................................................................33
9.2.2 Low Current (DC power supply)......................................................................................................................35
9.3 CHARGE FAILURE...............................................................................................................................................37
9.4 KEYBOARD FAILURE..........................................................................................................................................38
9.5 VIBRATION FAILURE...........................................................................................................................................39
9.6 SIM CARD FAILURE...........................................................................................................................................40
9.7 SD CARD FAILURE.............................................................................................................................................41
9.8 DISPLAY FAILURE...............................................................................................................................................42
9.9 TOUCH PANEL FAILURE.....................................................................................................................................43
9.10 CAMERA FAILURE ............................................................................................................................................44
9.11AUDIO FAILURE.................................................................................................................................................45
9.11.1 No Ring Tone..........................................................................................................................................................45
9.11.2 Voice Transmitting Failure................................................................................................................................46
9.11.3 Receiver Failure....................................................................................................................................................47
9.11.4 Earphone No Voice .............................................................................................................................................48
9.11.5 Earphone Can’t Transmit Voice.....................................................................................................................49
9.12 FM FAILURE......................................................................................................................................................50
9.13 WIFI FAILURE...................................................................................................................................................51
9.14 BT FAILURE.......................................................................................................................................................53
9.15 GPS FAILURE...................................................................................................................................................55
9.16 RF FAILURE......................................................................................................................................................57
9.16.1 RF Receiving Failure-WCDMA 2100MHz................................................................................................58
9.16.2 RF Receiving Failure-WCDMA 900MHz..................................................................................................59
9.16.3 RF Receiving Failure-GSM.............................................................................................................................60
9.16.4 RF Transmitting Failure-WCDMA 2100MHz ..........................................................................................61

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9.16.5 RF Transmitting Failure-WCDMA 900MHz.............................................................................................62
9.16.6 RF Transmitting Failure-GSM........................................................................................................................63
10 WELD POINTS INDICATOR CHART FOR PCB AND BGA CHIP ......................................................64
11 FUNCTIONAL TEST............................................................................................................................................66
11.1 KEYPAD INTRODUCTION .................................................................................................................................66
11.2 MMI TEST..........................................................................................................................................................66
11.3 VOICE CALL TEST............................................................................................................................................68

U8350 Maintenance Manual Basic Version V1.0
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1 Product Introduction
1.1 Product Appearance
1.2 Product Specifications
Items
Content Description
Shape
Bar-type
LCD
2.6-inch TFT-LCD capacitive touch screen with 320X240 (QVGA)
resolution,262k colors
Sensors
Accelerometer
Digital compass
Dimensions
115mm(L)×62.8mm(W)×9.9mm(H)
Weight
About 122g(including the battery)
Technical Standards
WCDMA/HSDPA: 3GPP FDD Release 99, Release 5 (International
standard,3GPP R5,)
GSM/GPRS/EDGE: 3GPP Release 99
Frequency band
WCDMA 2100 MHz: 1920-1980 MHz (UL), 2110-2170 MHz (DL)
WCDMA 900MHz: 880-915 MHz (UL), 925-960 MHz (DL)
GSM 850 MHz: 824-849 MHz (UL), 869-894 MHz (DL)
GSM 900 MHz: 880-915 MHz (UL), 925-960 MHz (DL)

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Items
Content Description
GSM 1800 MHz: 1710-1785 MHz (UL), 1805-1880 MHz (DL)
GSM 1900 MHz: 1850-1910 MHz (UL), 1930-1990 MHz (DL)
Network Access
3G-WCDMA /HSDPA /GPRS /EDGE
SIM/USIM card interface
standard 6-pin SIM card interface, supporting the 1.8/3V USIM card
External Interface
Standard Micro USB, MicroSD Card slot, 3.5mm headset
External Memory support
MicroSD Card (up to 32GB)
Processor
Qualcomm®MSM7225-1, 528MHz
Memory
ROM:512 MB,RAM:256MB
Device Control
QWERTY keys
Temperature
Operating temperature: -10°C ~ + 50°C (without charger)
Warehouse temperature: -40°C ~ +70°C
Battery
1200 mAh
Standby time: 300 hours (WCDMA) / 220 hours (GSM)
Talking time: 5 hours (WCDMA) / 4 hours (GSM)
Charging Time: About 2.5 hours
Relative humidity
working: 5% ~ 95%
Camera
3.2MFF Camera
Antenna
Built-in antenna
Bluetooth
V2.1+EDR
WiFi
WiFi 802.11b/g/n
USB
USB2.0 High Speed
Maximum transmit power
WCDMA 2100MHz/900MHz: +24dBm (Power Class 3)
GSM 850MHz/900MHz: +33dBm (Power Class 4)
GSM 1800MHz/1900MHz: +30dBm (Power Class 1)
Static sensitivity
WCDMA 900 MHz: better than -103.7 dBm/3.84 MHz
WCDMA 2100 MHz: better than-106.7 dBm/3.84 MHz
GSM 850 MHz: better than -102 dBm/200 kHz
GSM 900MHz: better than -102 dBm/200 KHz
DCS 1800MHz: better than -102 dBm/200 KHz
PCS 1900MHz: better than -102 dBm/200 KHz
Power supply
100-240V, 50/60Hz
Certification
BQB, WIFI, GCF, RoHS, REACH, CE

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2 Maintenance Information Guide
2.1 Document Application
This document provides instructions for maintenance of Huawei products. This manual is Huawei
proprietary and is only permitted to be used by authorized service partners. Shall there be any mistakes
found in this document, kindly contact our customer service personnel.
2.2 Maintenance Precautions
Maintenance and calibration can be conducted only by qualified technical personnel.
Always wear an antistatic wrist strap during operation in an antistatic room.
Ensure that all the components, screws, and insulators are properly installed after maintenance or
calibration. Ensure that all the cables are properly connected.
Ensure that the soldering should comply with the environmental requirements and lead-free.
2.3 Obtaining Maintenance Information
For more related product knowledge and maintenance information, please visit Huawei website
http://www.huaweidevice.com/worldwide/technicaIndex.do
Electrostatic discharging is the major cause for the damage of sensitive electronic
components. Each service site should attach great importance to the electrostatic
discharging and strictly observe the antistatic measures described in this manual.

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3 Explosive View of Product
This exploded view is only applied to show phone frame. It is not regarded as a reference for
applying spare parts.
No
Description
Quantity
1
Front_Cover_Asm,U8350
1
2
Bottom Cover Asm,U8350
1
3
BATT_Cover_Asm,U8350
1
4
Front_deco_asm,U8350
1
5
LCD_frame,U8350
1
6
Receiver_Metal_Net,U8350,Chrome
1
7
KEY_NUM_KEY_ASM,U8350
1
8
fun_KEY_ASM,U8350
1
9
VOL_KEY_asm,U8350
1
10
POWER_KEY_asm,U8350
1
11
mic_cover,U8350
1

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No
Description
Quantity
12
VOLUM_KEY_DOME,U8350
1
13
POWER_KEY_DOME,U8350
1
14
MAIN_KEY_DOME,U8350
1
15
SHIELD_FRAME_1,U8350
1
16
SHIELD_COVER_1,U8350
1
17
PCB_support,U8350
1
18
SIM_support,U8350
1
19
SPK_CU,U8350
2
20
batt_adhen,U8350
1
21
TP PROTECT FILM
1
22
Product_Nameplate
1
23
TP_IC_gasket
1
24
TP_Gasket,U8350
1
25
T5 pan head mechanical
screw,M1.4*3.5*D2.6*0.8,Plated with black zinc
6
26
Mechanical Screw
3
27
Staping screw ST1.4*3.5*D2.6*0.8
1
28
Disassemble(Φ2.5mm)-proof label
1
29
Waterproof Label-D3.0mm
2
30
PCB
1
31
LCD
Module,Single,TFT-LCD,2.55inch,320RGB*240,262K
Color Depth,3:4,2.3mm,Without Touch Screen,BTB
1
32
Battery
1
33
Touch Screen,M650,320*240,2.6V,59.00*58.20
1

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4 Location of Components on the Main Board
J1101 IO Connector
Failure symptom:
Charging failure. Data
communication failure.
J1102 Earphone
Connector
Failure symptom:
Earphone failure.
D1306 Transient
Suppressing Diodes
Failure symptom:
Touch panel failure.
U4102 SAW Filter
Failure symptom:
GPS failure.
U4101 RF LNA
Failure symptom:
GPS failure.
U4103 SAW Filter
Failure symptom:
GPS failure.
Z4304 SAW Filter
Failure symptom:
W2100MHz weak
signal.
Z1101 Varistor,
ESD+EMI Noise Filter
Failure symptom:
Earphone failure.
U1101 Earphone
Audio Power
Amplifier
Failure symptom:
Earphone failure.
U1701 AUDIO
Chip-FM Stereo Radio
SI4708
Failure symptom:
FM failure.
U601 FLASH, MCP
Failure symptom:
Can’t power on.
Software failure.
U401 CPU,
WCDMA/GSM
Dualmode
BASEBAND
PROCESSOR
MSM7225
Failure symptom:
Can’t power on. No
signal, weak signal.
Data communication
failure, etc.
U502 CMOS-8-D
Triggering Device
Failure symptom:
No power on. RF failure.
U202 LDO,3.3V
Failure symptom:
Data communication
failure.
U201 Power
Management IC
Failure symptom:
Can’t power on.
U901 Oscillating Motor
Failure symptom:
No vibration.

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U3801 WCMDA/GSM
Radio Transceiver
(RTR6285)
Failure symptom:
No signal, weak signal;
can’t register the
network.
U3401 Power Module,
880~915MHz
Failure symptom:
W900 can’t register the
network.
U3402 SAW Filter
897.5MHz
Failure symptom:
W900 can’t register the
network.
X301
Crystal-0.032768MHz
Failure symptom:
Can’t power on.
U3404 Duplexer,
TX:880~915MHz/
RX:925-960MHz
Failure symptom:
W900 no signal, weak
signal; can’t register the
network.
U3101 Temperature
Compensated Crystal
Oscillator-19.2MHz
Failure symptom:
Can’t power on.
U3301 SAW Filter-
1950MHz
Failure symptom:
W2100 can’t register
the network.
U3302 Power Module,
1920~1980MHz
Failure symptom:
W2100 can’t register
the network.
U3501 Power module
Failure symptom:
GSM can’t register the
network.
U3202 RF Switch,
824~960MHz/
1710~2170MHz
Failure symptom:
No signal, weak signal;
can’t register the
network.
U3304 Duplexer,
TX:1920~1980MHz/
RX:2110~2170MHz
Failure symptom:
W2100 no signal, weak
signal; can’t register the
network.
U3702 SAW
Filter-2140MHz
Failure symptom:
W2100MHz no signal,
weak signal.

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J1201 BTB
Connector,
Female,50Pin
Failure symptom:
LCD display failure.
U1201 Voltage
Regulator, Current
Mode
Failure symptom:
LCD backlight failure.
U1501 DCDC Control
Chip
Failure symptom:
Charging failure.
J1302 BTB
Connector-Female-
24Pin
Failure symptom:
Touch Panel failure;
volume key failure;
Power key failure.
U4601 Single chip WiFi,
802.11a/b/g/n-BCM4319
Failure symptom:
WiFi failure.
J1601 Connector, SIM
Card Socket
Failure symptom:
Can’t identify SIM card.
J1001 BTB
Connector-Female-
24Pin
Failure symptom:
Camera failure.
U1402 Semiconductor
Sensor,
Accelerometer
Failure symptom:
Gravity sensor failure.
J1303 BTB
Connector,Female,
10Pin
Failure symptom:
Keypad failure; voice
transmitting failure..
U4705 Ceramics
Filter, 2450MHz
Failure symptom:
WiFi failure. BT failure.
U4704 RF Switch,
10-3000MHz
Failure symptom:
WiFi failure. BT failure.
X4001 Crystal-32MHz
Failure symptom:
BT failure.
X4601 Crystal-26MHz
Failure symptom:
WiFi failure.
U4001 Bluetooth IC
chip BTS402
Failure symptom:
BT failure.
J1602 Card
Connecter, MicroSD
Receptacle
Failure symptom:
Can’t identify microSD
card.
J1501 Battery Socket
Failure symptom:
Can’t power on.
U3201 RF Connector
Failure symptom:
No signal, weak signal.
U1403 Semiconductor
Sensor, E-Compass
Failure symptom:
Compass failure.

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FPC
Failure symptom:
Keypad failure; voice
transmitting failure.
U201 Interface
Controller
Failure symptom:
Keypad failure.
DOME
Failure symptom:
Keypad failure.
MIC201 MIC
Failure symptom:
voice transmitting
failure.

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BOM List is only for your reference, the lasted BOM information is downloaded in the system of
Huawei.
BOM
Description
Location
15010251
Schottky Diode-30V-0.2A-0.5V-SOD523
D1301,D901
15040238
Transient Suppressing
Diodes-6V-14V-10W-12A-SOD882/0402
D1101,D1102,
D1501, D902,D903
15040208
Transient Suppressing
Diodes-6.8V-11.4V-75W-7A-SOT-363
D1306
19040121
Fast Blowout Fuse-32V-2A-IEC Spec-0.030 ohm-0.100
A*A*Sec-UL/CSA/ANSI 248 Certificated
F1101
14240181
BTB Connector-Fmale-24Pin-0.4mm-SMT-Mating Height
1.0mm
J1001,J1302
14240272
IO Connector,Micro_B-Female,5pin,Side Plugging
Type,SMT
J1101
14240246
Headphone Connector,3.5mm,6pin,Side
plugging,SMT,Mid Mount,1.85mm Height from PCB Top
Side,Arc type
J1102
14240226
BTB Connector,Female,50Pin,0.4mm,Mating Height
1.0mm,SMT,Width 3.74mm After Mating
J1201
14240199
BTB Connector,Female,10Pin,0.4mm,0.9mm
J1303
14240100
Connector,Battery Socket-3PIN-Side
Contact-2.8mm-1.4mm-With Position Peg
J1501
14240028
Connector,SIM Card Socket,6pin,Height 0.7mm
J1601
14240249
Card Connecter,MicroSD
Receptacle,8pin,PUSH-PUSH,1.1mm,Have
Lock,Without Hold Peg,1.45mm
J1602
51621895
Spring_Ant,U8300
J1802,J1803
51621274
Main Antenna SMT Spring-C5600
J3201,J3202,J3203,
J4101,J4102,J4301,
J4302,J4703,J4704
15060228
MOSFET,P
Channel,-12V,-2.4A,0.112ohm,8V,SOT-23(Split from
15060150)
Q202
07040061
Varistor-12V-99999V-5A-25V-SMT-0402-50pF@1kHz
R908,R909,
RV1301, RV1501
07040071
Varistor-90V-45V-1A-300V-SMT-0402-3pF@100MHZ
RV1101,RV1102
51622446
SHIELD_FRAME_1,U8350
S1801
51622448
PCB_support,U8350
S1802
51622449
SIM_support,U8350
S1803
51622450
SPK_CU,U8350
TP901,TP902
39200074
Terminal Dedicated IC,Power Management IC of
QUALCOMM MSM7200 Series
_PM7540,3.6V,BGA137(pb-free)
U201
39110548
LDO,3.3V,2%,0.2A,SC70-5
U202
39200160
WCDMA/GSM Dualmode BASEBAND PROCESSOR
MSM7225-1,1.2V/1.8V/2.6V,BGA456(Pb-Free)
U401
36020341
CMOS-8-D Triggering
Device-SC_70-20ns-24mA-CMOS-CMOS
U502

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BOM
Description
Location
40060281
MCP,4Gb(256Mx16)NAND
Flash,64K,1.8V,FBGA137(pb-free),2Gb(64Mx32)Mobile
DDR SDRAM
U601
32050031
Oscillating
Motor,SMT,2.7,75A,14000rpm,11mm*4.4mm*3.6mm,Null
,28ohm
U901
39080124
HeadphoneAudio Power Amplifier,2.3 V to 5.5
V,differential AB Amplifier,QFN
U1101
39110581
Voltage Regulator,Current Mode,Regulated Output
Current With 0.3% Matching,0.125A,16Pin QFN
U1201
38140023
Semiconductor Sensor,Accelerometer,LGA,3axis
U1402
38140024
Semiconductor
Sensor,E-Compass,WL-CSP(Pb-free),3axis
U1403
39110531
DCDC Control Chip,20pin,WCSP
U1501
43110047
AUDIO Chip-FM Stereo Radio SI4708-QFN
U1701
12070013
Temperature Compensated Crystal
Oscillator-19.2MHz-+/-2.5ppm-2.8V-+/-2.0ppm
U3101
14240004
Connector,RF Connector-Straight-Female-SMT
U3201
47140048
RF Switch,824~960MHz/1710~2170MHz,SP9T
FEM,1.2/1.35,1.8:1,QFN
U3202
13010186
SAW Filter-1950MHz-2.9-QCS5I
U3301
47100280
Power Module,1920~1980MHz,28,3x3 QFN
U3302
13080065
Duplexer,TX:1920~1980MHz/RX:2110~2170MHz,1.8dB,
2.2dB,50dB/42dB,2520
U3304
47100277
Power Module,880~915MHz,27.5,3x3 QFN
U3401
13010189
SAW Filter-897.5MHz-2.7dB-100V(MM)-SFLT5-0101
U3402
13080067
Duplexer,TX:880~915MHz/RX:925-960MHz,2.2dB,2.6dB
,57dB/48dB,2520
U3404
47100258
Power module,34.7dB/32.5dB,package
BCC11H-Terminal special
U3501
13010176
SAW Filter-2140MHz-1.9dB-1.4*1.1mm
U3702
39200084
Terminal Dedicated IC,WCMDA/GSM Radio
Transceiver(RTR6285),2.7V/2.6V/2.1V,mQFN68
U3801
39200164
Terminal dedicate IC, Bluetooth IC chip
BTS4025,1.8V/2.7V,BGA36 (Pb-free)
U4001
47090041
RF LNA-0.4~3GHz-15.7-0.95-QFN
U4101
13010180
SAW Filter-1575.42MHz-0.9dB-1.4*1.1mm
U4102,U4103
39200174
Terminal dedicated IC, Single chip
WiFi,802.11a/b/g/n-BCM4319,2.3V-5.5V,WLBGA138
(Pb-free)
U4601
47140046
RF Switch,10-3000MHz,SP3T,0.8,16,TSSON
U4704
13030038
Ceramics Filter,2450MHz,2.9dB,2.0*1.25*0.3mm
U4705
12020125
Crystal-0.032768MHz-12.5pF-+/-30ppm-60000ohm/8000
0ohm-3.2*1.5 SMD
X301
12020159
Crystal-32MHz-12pF-+/-10ppm-60ohm-SMD3225
X4001

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BOM
Description
Location
12020132
Crystal-26MHz-12pF-+/-10ppm-50ohm-SMD3225
X4601
07040064
Varistor-8V-4V-30V-SMT-0405-ESD+EMI Noise
Filter-DCR 0.3ohm/270pF@1MHz
Z1101
07040072
ESD_EMI Filter-14V-30pF-800~3000MHz-ARRAY-0603
Z1601
13010148
SAW Filter-2140MHz-50V-00231804
Z4304
03021ANH
Keypad Board,U8350
/
15020143
Lighting
Diode-1cd/1.6cd-White-30mA-3.8mm*1.2mm*0.6mm/Sid
e View
D202,D203
22050053
MIC--44dB.-D4.0mm*1.3 mm-SMT
MIC201
43140080
Interface Controller,18-GPIO port expander or 8 *10
keypad matrix, 1.65v,3.6V,QFN
U201
03021CAV
FPC,U8350
/
14240200
BTB Connector,Male,10Pin,0.4mm,Mating Height 0.9mm
J101
03021CAW
Sidekey FPC,U8350
/
14240180
BTB Connector-Male-24Pin-0.4mm-SMT-Mating Height
1.0mm
J101
14240199
BTB Connector,Female,10Pin,0.4mm,0.9mm
J102
22020058
Speaker-8ohm-0.5W-Spring Contact-RoHS-11mm*
15mm*3.5mm
/
23040172
LCD
Module,Single,TFT-LCD,2.55inch,320RGB*240,262K
Color Depth,3:4,2.3mm,Without Touch Screen,BTB
/
23060051
Camera Module-CMOS-2048*1536-FF-Narrow
BTB-6.5*6.5*4.1-5CA
/
22030036
Receiver,32 ohm,10mw,6*15*2.5mm,receiver no
adhesion
/
51633150
mic_cover,U8350
/
23070068
Touch Screen,M650,320*240,2.6V,59.00*58.20
/
51622442
VOLUM_KEY_DOME,U8350
/
51622443
POWER_KEY_DOME,U8350
/
51622444
MAIN_KEY_DOME,U8350
/

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5 Software Upgrade
5.1 Preparation for Upgrade
Item
Contents
Remark
Upgrade Environment
Battery
The battery level shall be no less than two bars.
Micro SD card
512M at least.
PC
For copy upgrade file.
Upgrade packages
Main package
The version is only for your information. Please
download the latest version.
Vender package
Please download the location version.
Upgrade mode
SD card upgrade
Normal download & Force Download.
5.2 Upgrade Process
1. Format micro SD card or delete its content;
2. Create a folder and named as “dload” to the root directory of the MICRO SD card, copy the software
“updata.app”to the dload folder;
3. Insert micro SD card，enter Dialer interface, input *#*#2846579#*#*, operate as follows:
ProjectMenu→7. Upgrade→1. SD card upgrade→Confirm

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4. Begin upgrade the main package, the handset will restart automatically.
5. Upgrade the vender package. The upgrade procedure is the same as upgrade main package.

U8350 Maintenance Manual Basic Version V1.0
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2011-05-18
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5.3 Force Download
1. Format micro SD card or delete its content.
2. Create a folder and named as “dload”, copy “updata.app” into it.
3. Make sure your handset is power off, Insert micro SD card into the handset.
4. Pressing End Key and Volume up Key, and then press Power Key to enter force download.
5. After upgrade completed, the handset will restart automatically.

U8350 Maintenance Manual Basic Version V1.0
Internal
2011-05-18
Huawei confidential. No spreading without permission.
Page 20 of 68
5.4 Check the Firmware Version
To check the version
Settings -> About phone -> Build number
5.5 Error Handling
Error 1
During SD card upgrade, the key pad led flash very frequently (two flashes per second), and the
progress bar stop, that means an error occurs. Check whether there is a miss-operation. You can
change another phone or SD card to do the test.
Error 2
If you find below picture displayed in the screen of your phone, that means something wrong happened.
Check whether there is a miss-operation. You can change another phone or SD card to do the test.
Notes:
To make sure that the power of the battery is enough to run the upgrade process. Maybe you can
connect the handset with the charger or the USB data cable to provide power.