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Product Department
Documentation Team
Product Department
Technology Support Engineer
Product Department Service
Representative of product
E5331 Maintenance Manual Basic Version
V1.0
Huawei Technologies Co., Ltd.
All rights reserved
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E5331 Maintenance Manual Basic Version V1.0
Huawei confidential. No spreading without permission.
Product Department
Documentation
Team
Revision Record
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E5331 Maintenance Manual Basic Version V1.0
Huawei confidential. No spreading without permission.
Contents
1 PRODUCT INTRODUCTION ............................................................................................................................................ 5
1.1 PRODUCT APPEARANCE ................................................................................................................................................ 5
1.2 HARDWARE SPECIFICATIONS ....................................................................................................................................... 5
2 MAINTENANCE INSTRUCTIONS ................................................................................................................................... 7
2.1 DOCUMENT APPLICATION ............................................................................................................................................ 7
2.2 MAINTENANCE PRECAUTIONS ..................................................................................................................................... 7
2.3 MAINTENANCE INFORMATION DIRECTION .................................................................................................................. 7
3 EXPLODED VIEW OF THE WHOLE UNIT .................................................................................................................... 8
4 LOCATION OF COMPONENTS ON THE MAIN BOARD ............................................................................................ 9
5 SOFTWARE UPGRADE .................................................................................................................................................. 12
5.1 PREPARATIONS BEFORE UPGRADE ............................................................................................................................ 12
5.2 HARDWARE CONNECTION ........................................................................................................................................... 12
5.3 CLIENT SOFTWARE INSTALLATION ............................................................................................................................ 12
5.4 UPDATE PROCEDURE .................................................................................................................................................. 19
5.4.1 Normal Upgrade ............................................................................................................................................ 20
5.5 CHECK THE SOFTWARE VERSION .............................................................................................................................. 22
5.6 EXCEPTION HANDLING ............................................................................................................................................... 22
6 MAINTENANCE TOOLS ................................................................................................................................................. 24
7 DISASSEMBLY PROCEDURE ................................................................................................................................ ....... 26
8 ASSEMBLY PROCEDURE ............................................................................................................................................. 28
9 TROUBLESHOOTING FOR COMMON FAULTS ........................................................................................................ 30
9.1 PRINCIPLE INSTRUCTION ........................................................................................................................................... 30
9.2 NO POWER ON ............................................................................................................................................................. 31
9.2.1 No Power On—High Current (DC Power Supply) ...................................................................................... 31
9.2.2 No Power On—Small Current (DC Power Supply) ..................................................................................... 34
9.3 CHARGE FAILURE ....................................................................................................................................................... 36
9.4 SIM CARD FAILURE .................................................................................................................................................... 37
9.5 DATA COMMUNICATION FAILURE .............................................................................................................................. 38
9.6 DISPLAY FAILURE ........................................................................................................................................................ 40
9.7 WLAN FAILURE ......................................................................................................................................................... 42
9.8 RF FAILURE................................................................................................................................................................. 44
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E5331 Maintenance Manual Basic Version V1.0
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9.8.1 RF Receiving Failure – WCDMA 2100MHz ................................................................................................ 44
9.8.2 RF Receiving Failure – WCDMA 900MHz .................................................................................................. 46
9.8.3 RF Receiving Failure – GSM........................................................................................................................ 47
9.8.4 RF Transmitting Failure – WCDMA 2100MHz ........................................................................................... 48
9.8.5 RF Transmitting Failure – WCDMA 900MHz ............................................................................................. 49
9.8.6 RF Transmitting Failure – GSM .................................................................................................................. 50
10 WELD POINTS INDICATOR CHART FOR PCB ..................................................................................................... 51
11 FUNCTIONAL TEST .................................................................................................................................................... 54
11.1 APPEARANCE INTRODUCTION .................................................................................................................................... 54
11.2 DATA SERVICE ............................................................................................................................................................. 55
11.2.1 USB Modem..................................................................................................................................................... 55
11.2.2 Wireless Modem ............................................................................................................................................. 55
11.3 INTERNET TEST ........................................................................................................................................................... 57
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E5331 Maintenance Manual Basic Version V1.0
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WAN: HSPA+/HSPA/UMTS/EDGE/GPRS/GSM
WLAN: IEEE 802.11b/g/n
Operating frequency
HSPA+/HSPA/UMTS
EDGE/GPRS/GSM: 1900/1800/900/850MHz
Maximum transmitter
power
WLAN (Power adapter mode)
WLAN 802.11b: -76dBm@11Mbps/-82dBm@1Mbps
WLAN 802.11g: -65dBm@54Mbps
WLAN 802.11n: -64dBm@65Mbps
1.1 Product Appearance
1 Product Introduction
1.2 Hardware Specifications
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E5331 Maintenance Manual Basic Version V1.0
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802.11n: Support MCS0–MCS7; Up to 72.2Mbit/s.
Maximum power
consumption
AC: 100V–240V
DC: 5V, 1A
Type: Li (Rechargeable)
Capacity: 3.7 V, 1500 mAh
Maximum working time: 4.5 hours
Maximum standby time: 150 hours while Wi-Fi is off; 30 hours while Wi-Fi is often
on.
External interfaces
USB interface: Micro USB
SIM card: standard 6-pin SIM card interface
Built-in GSM/UMTS main diversity antenna
Built-in UMTS diversity antenna
Built-in WLAN antenna
about 83g (including the battery)
Operating: 0℃ to +35℃
Storage: –40℃ to +70℃
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E5331 Maintenance Manual Basic Version V1.0
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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.
2 Maintenance Instructions
2.1 Document Application
This document provides instructions for the maintenance of Huawei products for the maintenance personnel in
Huawei-authorized service sites. This manual is Huawei proprietary and is only permitted to be used by
authorized service sites or companies. Mistakes may be found in the document. If you have found any mistake
or have any suggestion, please 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 the operation and conduct the maintenance 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 is lead-free.
2.3 Maintenance Information Direction
To obtain related product knowledge and maintenance information, please visit Huawei website
http://www.huaweidevice.com/worldwide/technicaIndex.do
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E5331 Maintenance Manual Basic Version V1.0
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3 Exploded View of the Whole Unit
This exploded view is only applied to show phone frame. It is not regarded as a reference for applying
spare parts.
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E5331 Maintenance Manual Basic Version V1.0
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X3501 Crystal
Units,32.768kHz
Failure Symptom:
No power on
Z901&Z902 Diversity
Receive SAW FILTER
-W900MHz &W2100MHz
Failure Symptom:
U3201 FLASH
Failure Symptom:
No power on;
Others software failure
Z603&Z602SAW FILTER
–W900MHz&W2100MHz
Failure Symptom:
Weak signal
U3801 Battery
Management IC
Failure Symptom:
Charge failure
TCXO301 TCXO,26MHz
Failure Symptom:
No power on
U3101 CPU
Failure Symptom:
No power on,
Others failure
U3501 PM
Failure Symptom:
No power on
Z501&Z401SAW FILTER
–W900MHz&W2100MHz
Failure Symptom:
TX failure
U3601 Voltage
Regulator
Failure Symptom:
RF Failure - WCDMA
X4001 Crystal
Osillator,26MHz
Failure Symptom:
WiFi Failure
U4102 RF Switch
Failure Symptom:
WiFi Failure
U4001 WIFI IC
Failure Symptom:
WiFi Failure
Z4101 Ceramics Filter
2450MHz
Failure Symptom:
WiFi Failure
U901 Duplexer
–W2100MHz&W900MHz
Failure Symptom:
U101 RF Transceiver
Failure Symptom:
RF Failure
U501 Power Module
–W2100MHz
Failure Symptom:
RF Transmitting
U401 Power Module
–W900MHz
Failure Symptom:
RF Transmitting Failure
U402 Duplexer
-W2100MHz
Failure Symptom:
RF Failure
U502 Duplexer
–W900MHz
Failure Symptom:
RF Failure
U801
Front End Module
Failure Symptom:
RF Failure
U703 SPDT
Failure Symptom:
RF Failure
Z701 SAW FILTER
–W900MHz
Failure Symptom:
RF Transmitting Failure
Z702 SAW FILTER
–W850MHz
Failure Symptom:
RF Transmitting Failure
S3501
POWER BUTTON
Failure Symptom:
No power on
4 Location of Components on the Main Board
Take E5331 for example:
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E5331 Maintenance Manual Basic Version V1.0
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NTC,10000ohm,NTC,SMD,0402,B=3380K,TS16949
Thermistor,150kohm+/-5%,SMT,0402
Varistor,18V,14V,10A,40V,SMT,0402,82pF@1KHz
Varistor,90V,45V,1A,300V,SMT,0402,3pF@1MHz
RV4101,RV4102,RV4103,
RV4104,RV4105,RV4106
Touch switch-SPST-12V(DC)-0.05A-SMT-0.6mm-5*2.5-100000-for
Mobile phone side key
TCXO,26MHz,+/-1.5ppm(max),+2.85V,+/-1.5ppm(max),30degC,+80d
egC
Consumption Chip,Hi6331RBCV301,STFBGA,2.85V/1.8V,2G/3G
Multi mode and Multi band RF Transceiver
Consumable Chip,Hi6481RBCV150,TFBGA,3.3/5V,Average Input
Current Limit,Six Bucks E5
MCP,1Gb(128Mb*8) NAND
FLASH,166MHz,128KB,1.8V,FBGA107(Pb-free),512Mb(32Mb*16)
DDR
Power Module,1920-1980MHz,27dB,28dBm,QFN,1000V
Duplexer,TX:1920~1980MHz/RX:2110~2170MHz,1.8dB,2.2dB,50dB/
42dB,2520
0.5~3GHz,SPDT,0.46,22,TSSON
U1004,U1204,U601,U702,
U703,U902
RF Power Amplifying
Module,824MHz~849MHz/880MHz~915MHz/1710MHz~1785MHz/18
50MHz~1910MHz,33.5,35dBm,LGA
RF Switch,
824-2170MHz,SP10T,0.65-1.2dB,1.5,18dB/58dB,QFN,200~260V(HB
M),Termnal Dedicated
DKBA8.382.0693,U7519_Antenna_Pin,U7519
LVCMOS,Unbuffer Single Inverter
Gate,SC-70,9.0ns,4.0mA,CMOS,CMOS
0.5~2.5GHz,SP4T,0.95,15,QFN
RF Power Amplifying Module,880MHz~915MHz,28/18/11,QFN,1000V
Duplexer,TX:880~915MHz/RX:920~960MHz,3dB.,3.5dB.,47dB./38dB
.,2.5*2.0*0.5mm
BOM List is only for your reference, the lasted BOM information is downloaded in the system of
Huawei.
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E5331 Maintenance Manual Basic Version V1.0
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Consumable
Chip,Hi6755RBCV120,SVFBGA,1.2/2.5V,WCDMA/HSPA
Communication Baseband Function,SOC Support Dual Mode PS
Switching Regulators,1~4V,1.5A,SMT
Terminal Dedicated IC,WIFI 802.11bgn,1.8V~3.3V,BGA97(Pb-Free)
RF Switch,DC~3000MHz,SPDT,0.6dB,1.4,20dB,SOP6-26-50,250V
Battery Management IC,4.1~16V,DC-DC Charger,Smart Power
Control,QFN,SMT
Voltage Regulator,Vin~20V,0.7A,5-Pin SOT23
Crystal Units,32.768kHz,12.5pF,20ppm,65kohm,SX4
Crystal Osillator,26MHz,12pF,+/-10ppm,50ohm,SMD3225
SAW Filter,881.5MHz/942.5MHz,2.5dB/3.0dB,50V,1814
SAW filter,2140MHz,1.9dB,1.4*1.1mm
SAW FILTER,897.5MHz,2.7dB,100V(MM),SFLT5-0101
SAW Filter,836.5MHz,2.1dB,50V,1.4*1.1mm,TS16949
SAW Filter,881.5MHz/942.5MHz,2.5dB/3.2dB,50V,1814
SAW Filter,1842.5MHz/1960MHz,3.0dB/3.0dB,50V,1814
SAW Filter ,2140,3.0dB,50V,00231804
SAW FILTER,(925~960)MHz,2.1dB,100v,SFLT5-0101
Ceramics Filter,2450MHz,2.30dB,2.5*2.0*1.3mm
Power Module, 824MHz~849MHz,27dB,28.5dBm
Duplexer,TX:824MHz~849MHz/RX:869MHz~894MHz
ceramic filter,869.5MHz,0.65 dB,ESD
SAW Filter,836.5MHz,2.1dB,50V,1.4*1.1mm
ESD_EMI Filter,14V,30pF,800~3000MHz,ARRAY,0603
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E5331 Maintenance Manual Basic Version V1.0
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E5331 Mobile WiFi Firmware
v3.6.exe
Firmware software
(The client software is just for you information,
please download the newest software to upgrade )
Upgrade mode
Normal upgrade
Windows XP / Windows 7/ Vista
5 Software Upgrade
5.1 Preparations Before Upgrade
5.2 Hardware connection
5.3 Client Software Installation
1. Power on the E5331.
2. Connect the E5331 to the PC with USB data cable.
3. Double click the “MobileWiFi”.
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E5331 Maintenance Manual Basic Version V1.0
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4. Click “Next” to continue.
5. Click “I Agree” to continue.
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6. Click “Install” to continue.
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7. The installation is completed. Click “Finish” to close the window.
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8. Power on the wireless modem. Then connect the wireless modem to the PC with USB data cable. Access
the “Device Management” to check if the connection between the wireless modem and the PC is well.