Huawei Release Notes F Tanjim Qmobile Call Centre Singer Y200 U8655 1. 51053288 U8655N(MTC965) Maintenance Manual V1.0

U8655N

Maintenance Manual

Issue

1.0

Date

2012-09-27

HUAWEI TECHNOLOGIES CO., LTD.

Issue 1.0 (2012-02-23)

Huawei Proprietary and Confidential

i

No part of this document may be reproduced or transmitted in any form or by any means without prior

written consent of Huawei Technologies Co., Ltd.

Trademarks and Permissions

and other Huawei trademarks are trademarks of Huawei Technologies Co., Ltd.

All other trademarks and trade names mentioned in this document are the property of their respective

holders.

Notice

The purchased products, services and features are stipulated by the contract made between Huawei and

the customer. All or part of the products, services and features described in this document may not be

within the purchase scope or the usage scope. Unless otherwise specified in the contract, all statements,

information, and recommendations in this document are provided "AS IS" without warranties, guarantees or

representations of any kind, either express or implied.

The information in this document is subject to change without notice. Every effort has been made in the

preparation of this document to ensure accuracy of the contents, but all statements, information, and

recommendations in this document do not constitute a warranty of any kind, express or implied.

Huawei Technologies Co., Ltd.

Address:

Huawei Industrial Base

Bantian, Longgang

Shenzhen 518129

People's Republic of China

Website:

http://www.huawei.com

Email:

support@huawei.com

U8655

Maintenance Manual

About This Document

Issue 1.0 (2012-02-23)

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About This Document

Purpose

Prepared by

R&D

Date

Reviewed by

Maintenance support team

Date

Approved by

Service representative

Date

Change History

Date

Version

Change Reason

Revised Section

Description

Author

2012-02-20

V1.0

Released the first issue.

R&D

U8655

Maintenance Manual

Contents

Issue 1.0 (2012-02-23)

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Contents

About This Document .................................................................................................................... ii

1 Product Introduction .................................................................................................................... 1

1.1 Appearance ....................................................................................................................................................... 1

1.2 Specifications ................................................................................................................................................... 1

2 Applicable Scope and Precautions ............................................................................................ 3

2.1 Applicable Scope .............................................................................................................................................. 3

2.2 Precautions ....................................................................................................................................................... 3

2.3 How to Obtain Product and Repair Information .............................................................................................. 3

3 Exploded View............................................................................................................................... 4

4 Components on the PCBA ........................................................................................................... 6

5 Software Upgrade ......................................................................................................................... 8

5.1 Upgrade Preparation ......................................................................................................................................... 8

5.2 Upgrade Procedure ........................................................................................................................................... 8

6 Maintenance Tools ...................................................................................................................... 10

7 Disassembly Procedure .............................................................................................................. 12

8 Assembly Procedure ................................................................................................................... 17

9 Principles and Failure Analysis ............................................................................................... 21

9.1 Block Diagram ............................................................................................................................................... 21

9.1.1 Function Description of the PCBA ....................................................................................................... 22

9.2 Baseband Unit ................................................................................................................................................ 25

9.2.1 Power-on Management Circuits ............................................................................................................ 25

9.2.2 Charging Management Circuits ............................................................................................................ 29

9.3 RF Unit ........................................................................................................................................................... 30

9.3.1 RF Failure ............................................................................................................................................. 30

9.3.2 GPS ....................................................................................................................................................... 33

9.3.3 Wi-Fi/Bluetooth/FM Module ................................................................................................................ 33

9.4 Peripheral Circuits .......................................................................................................................................... 34

9.4.1 Display .................................................................................................................................................. 34

9.4.2 Camera .................................................................................................................................................. 37

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9.4.3 USB ....................................................................................................................................................... 39

9.4.4 Headset Jack.......................................................................................................................................... 40

9.4.5 Keys ...................................................................................................................................................... 42

9.4.6 Status Indicator and Touch Key Backlight Circuits .............................................................................. 43

9.4.7 Battery Connector ................................................................................................................................. 44

9.4.8 Accelerometer ....................................................................................................................................... 45

9.4.9 Proximity and Illuminance Sensor ........................................................................................................ 45

9.4.10 Vibration Motor ................................................................................................................................... 47

9.4.11 Receiver .............................................................................................................................................. 48

9.4.12 Microphone ......................................................................................................................................... 50

9.4.13 Touchscreen Panel ............................................................................................................................... 51

9.4.14 SIM Card ............................................................................................................................................. 52

9.4.15 microSD Card ..................................................................................................................................... 53

9.4.16 NFC ..................................................................................................................................................... 54

10 Solder Points on the PCB and BGA Chip............................................................................. 59

11 Functional Tests......................................................................................................................... 64

11.1 MMI Test ...................................................................................................................................................... 64

11.2 Voice Call Test .............................................................................................................................................. 67

U8655

Maintenance Manual

1 Product Introduction

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1 Product Introduction

1.1 Appearance

1.2 Specifications

Category

Description

Dimensions (H x W x D)

116.9 mm x 61.4 mm x 12.2 mm

Technical standard

U8655N: W2100/W900, GSM850/900/1800/1900

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Category

Description

Frequency bands

U8655N:

- WCDMA 900MHz: 880–915 MHz (UL), 925–960 MHz (DL))

- WCDMA 2100 MHz: 1920–1980 MHz (UL), 2110–2170 MHz (DL)

- GSM 850 MHz: 824–849 MHz (UL), 869–894 MHz (DL)

- GSM 900 MHz: 880–915 MHz (UL), 925–960 MHz (DL)

- GSM 1800 MHz: 1710–1785 MHz (UL), 1805–1880 MHz (DL)

- GSM 1900 MHz: 1850–1910 MHz (UL), 1930–1990 MHz (DL)

Weight

< 125 g with battery

Form factor

Bar

Antenna

Built-in

UIM

SIM, USIM

Charger

5 V, 1000 mA

Battery

Type: Li-ion

Capacity: 1250 mAh

Standby time: 220–250 hours (network dependent)

Talk time: 210 minutes (network dependent)

Display

Resolution

320 x 480 pixels

Type

TFT LCD

Color

262K

Size

3.5 inches

Connectors

Charging port

micro-USB connector

USB port

micro-USB connector

microSD card

interface

microSD card interface

Headset jack

3.5 mm (LRGM)

Maximum

transmission

power

23–33 dBm

Static

sensitivity

≤ 104 dBm

Temperature

Operating temperature: 0°C to +40°C

Storage temperature: –20°C to +50°C

Humidity

Operating humidity: 5% to 95% RH

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Maintenance Manual

2 Applicable Scope and Precautions

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2 Applicable Scope and Precautions

2.1 Applicable Scope

This document provides repair instructions for technicians at service centers authorized by

Huawei. This maintenance manual is confidential and accessible to authorized service centers

(ASCs) and authorized service providers (ASPs) only. While every effort has been made to

ensure the accuracy of this document, errors may still exist. If you find any errors or have any

suggestions, please contact Huawei’s customer service.

2.2 Precautions

- Only qualified technicians are allowed to perform repair and calibration.

- Perform all operations in electrostatic discharge (ESD) rooms and wear ESD wrist straps

throughout the operations.

- Ensure that all components, screws and insulators are properly installed after repair and

calibration, and that all cables and wires are installed and connected correctly.

- Ensure that the soldering is lead-free and compliant with eco-friendly requirements.

2.3 How to Obtain Product and Repair Information

To obtain description and repair information about Huawei's products, please visit

http://www.huaweidevice.com/worldwide/technicaIndex.do.

ESD is the main cause of damage to electrostatic-sensitive components. Each

ASC must exercise caution to avoid ESD damage and comply with the ESD

protection requirements in this manual.

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3 Exploded View

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3 Exploded View

The components listed in the following table are structural parts of the phone, and cannot be

used as reference when requesting spare parts.

Table 3-1 List of components in the exploded view drawing

No.

Item

Quantity

1

U8655N_Cover A assembly

1

2

Touchscreen panel

1

3

U8655N_Cover B assembly

1

4

U8655N_Battery cover assembly

1

5

U8655N_Volume key

1

5

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No.

Item

Quantity

6

U8655N_Speaker shielding cover

1

7

U8655N_CPU shielding cover

1

8

U8655N_RTR shielding cover

1

9

U8655N_PA shielding cover

1

10

U8655N_Proximity and illuminance sensor sealing sheath

1

11

U8655N_MIC_sheath

1

12

U8655N_LCD_conductive fabric

2

13

U8655N_Headset insulation film

1

14

U8655N_USB_adhesive film

1

15

Screw M1.4*3.5

1

16

Diversity antenna and Wi-Fi antenna

1

17

Bluetooth antenna

1

18

Main antenna

1

19

LCD

1

20

Power key flexible flat cable (FFC)

1

21

Receiver

1

22

PCBA

1

23

Volume key FFC

1

24

Camera

1

25

Speaker

1

26

Battery

1

27

NFC antenna

1

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4 Components on the PCBA

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4 Components on the PCBA

J1001camera connector

Failure of this component

can cause:

Camera shooting failure.

J1401 SIM card holder

Failure of this component

can cause:

SIM card failure.

J1402 SD card holder

Failure of this component

can cause:

SD card failure.

U601 Flash memory chip

Failure of this component

can cause:

Power-on failure, software

are malfunction.

U401 CPU, MSM7225A

Failure of this component

can cause:

Power-on failure, phone

system crash, RF failure.

U4401 NFC module

Failure of this component

can cause:

NFC function failure.

U3302 power module, PA

Failure of this component

can cause:

W2100MHz transmission

failure.

U902 motor

Failure of this component

can cause:

Vibration failure.

U3304 duplexer

Failure of this component

can cause:

W2100MHz transmission

and reception failure.

U1402 SD card filter

Failure of this component

can cause:

SD card failure.

U1303 voltage regulator

Failure of this component

can cause:

LCD backlight failure.

U6000 Wi-Fi/Bluetooth/FM

3-in-1 chip

Failure of this component

can cause:

WiFi, Bluetooth and FM

failure.

U201 power management

chip, PM8029

Failure of this component

can cause:

Power-on failure.

X301 crystal oscillator

32.768KHz

Failure of this component

can cause:

Power-on failure.

J1605 ZIF connector

Failure of this component

can cause:

Volume key failure.

U1204 accelerator

Failure of this component

can cause:

Accelerator failure.

U3202 RF switch

Failure of this component

can cause:

RF failure.

U3201 RF connector

Failure of this component

can cause:

RF failure.

J1101 headset jack

Failure of this component

can cause:

Headset failure.

J1601 BTB connector

Failure of this component

can cause:

Touchscreen panel failure.

J902 battery connector

Failure of this component

can cause:

Power-on failure.

U4101 GPS LNA

Failure of this component

can cause:

GPS failure.

J11302 BTB connector

Failure of this component

can cause:

Display failure.

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U1207 proximity and

illuminance sensor

Failure of this component

can cause:

Proximity and illuminance

detection failure.

U3404 duplexer

Failure of this component

can cause:

W900MHz transmission

and reception failure.

U3501 power module, PA

Failure of this component

can cause:

GSM transmission failure.

J901 IO connector

Failure of this component

can cause:

Charging failure.

data communication failure.

D1200 tricolor indicator

Failure of this component

can cause:

Tricolor indicator failure.

F901 fuse

Failure of this component

can cause:

Charging failure.

U3401 power module, PA

Failure of this component

can cause:

W900MHz transmission

failure.

U901 DCDC control chip

Failure of this component

can cause:

Charging failure.

U3801 WCDMA/GSM

transmission and

reception chip

Failure of this component

can cause:

RF failure.

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5 Software Upgrade

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5 Software Upgrade

5.1 Upgrade Preparation

Category

Item

Description

Upgrade

environment

Computer

To copy upgrade software

microSD card

With more than 512 MB free space

Battery

With at least 30% power remaining

Upgrade file

Main upgrade pack

dload/UPDATE.APP

Vendor upgrade pack

vendor_XXX_XXX/UPDATE.APP

Upgrade

method

Using the microSD card

Normal upgrade

Forcible upgrade

5.2 Upgrade Procedure

1. Format the microSD card.

2. Create a folder named dload in the root directory of the microSD card.

3. Copy the upgrade file to the dload folder.

4. Install the microSD card on the phone. Power the phone on, and enter *#*#2846579#*#*

on the idle screen.

5. Select SD Upgrade then Yes to start the upgrade.

6. Before the upgrade, NV items backup is performed (if the phone's NV items has not

been backed up before). Then the phone restarts and the upgrade starts.

7. The upgrade progress is displayed on the LCD.

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8. After the upgrade is completed, the phone restarts and the NV items are restored.

9. After the main upgrade pack is upgraded, upgrade the vendor upgrade pack using the

same upgrade method.

If the phone cannot be properly powered on, use one of the following two methods to forcibly

upgrade the phone:

- Install the battery on the phone (if the screen is jittering, remove the battery and wait for

five seconds before installing the battery again). Press and hold the Volume+ and

Volume– keys, and press the Power key. The phone enters the SD forcible upgrade mode

in which the upgrade process is similar to the normal upgrade.

- While the phone has no battery installed, press and hold the Volume+ and Volume– keys,

and connect the charger to the phone.

The phone enters the SD forcible upgrade. This method is recommended. If the forcible

upgrade still fails, use another microSD card and try forcible upgrade again.

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6 Maintenance Tools

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6 Maintenance Tools

Name: constant-temperature hot air blower gun

Usage: to heat components

Name: constant-temperature heat gun

Usage: to heat components

Name: soldering iron

Usage: to solder components

Name: DC regulated power supply

Usage: to supply DC power

Name: soldering table

Usage: to secure the main PCBA

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Name: lead-free solder wire

Usage: soldering

Name: digital multimeter

Usage: to measure during repair

Name: toolkit

Usage: to assemble and disassemble components

Name: electric screwdriver

Usage: to fasten and remove screws

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7 Disassembly Procedure

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7 Disassembly Procedure

1. Wear an ESD wrist strap, and ensure that the strap is

grounded properly.

2. Remove the battery cover: Press the upper part of

the battery cover and push it towards the bottom.

3. Remove the battery.

U8655N before disassembly

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4. Remove the six screws from cover B.

5. Use the disassembly tab to release the latch in the

upper right corner.

6. Use the disassembly tab to release the latch in the

upper left corner.

7. Use a cover opener to release the latches between

cover A and cover B.

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7 Disassembly Procedure

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13. Remove the proximity and illuminance sensor

sheath and the microphone sheath.

11. Release the two latches in the PCBA.

10. Disconnect the BTB connector cable between the

touchscreen panel and the LCD.

8. Remove the volume key.

9. Release the volume key FPC.

12. Remove the PCBA.

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16. Apply a protective film on the LCD.

14. Release the BTB connector, and remove the

camera. Release the ZIF connector, and remove the

volume key FPC.

15. Release the LCD latches, and remove the LCD.

17. Apply a protective film on the inner side of the

touchscreen panel.

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19. Remove the receiver.

20. Remove the speaker.

21. The phone is now disassembled.

18. Remove the Power key FPC.

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8 Assembly Procedure

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8 Assembly Procedure

U8655N before assembly

1. Wear an ESD wrist strap, and ensure that the strap is

grounded properly.

2. Install the camera on the PCBA, and snap the BTB

connector in place. Install the volume key FPC into the

ZIF connector, and attach the adhesive film.

3. Install the receiver.

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4. Install the Power key FPC.

5. Remove the protective film from the touchscreen

panel.

6. Remove the protective film from the LCD.

7. Install the LCD. Ensure that the two latches are

snapped in place and that the LCD is even.

8. Install the PCBA: Insert the USB port into cover A,

and then snap the PCBA downward in place.

9. Gently press the PCBA to close the latches to secure

the PCBA.

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14. Install the six screws into cover B.

10. Snap the LCD's BTB connector and then the

touchscreen panel's BTB connector in place.

11. Install the volume key: Attach the volume key FPC

to the metal piece on cover A, and then install the

volume key.

12. Install the speaker.

15. Install the battery: Insert it into the battery

compartment bottom first.

13. Install cover B: Snap cover B's bottom, and press

its top.

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17. The phone is now assembled.

16. Install the battery cover.

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9 Principles and Failure Analysis

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9 Principles and Failure Analysis

9.1 Block Diagram

The MSM7X2XA (the U8655N uses the MSM7225A) is the baseband signal processing chip,

mainly responsible for processing the input and output of IMGE, VIDEO, AUDIO, MEMEO

SUPPORT, RF INTERFACES, and CONECTIVITY signals. The baseband chip provides

keypad, LCD, SD card, Wi-Fi, Bluetooth, camera, and microphone interfaces.

The PM8029 is mainly responsible for:

Detecting the connection and disconnection of the external power supply.

Supplying power to the phone.

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Providing analog multi-channel switch, real-time clock circuit, TCXO clock circuit, motor

driver circuit, and speaker driver circuit.

The RTR6285A is the RF signal processing chip, responsible for converting UMTS/GSM

uplink/downlink RF signals and using I/Q signals to exchange data with the baseband chip.

9.1.1 Function Description of the PCBA

The PCBA can be divided into four sub-systems: baseband, RF, power supply, and user

interfaces. The following table describes the subsystems' modules and units, as well as their

functions.

Table 9-1 PCBA subsystems' modules, units, and functions

Subsystem

Module

Unit

Function

Baseband

subsystem

MSM7225A

Modem subsystem

The modem subsystem includes the ARM11

processor, modem DSP, modem AHB bus,

interruption controller, and sleep controller.

The ARM9 is a 400 MHz modem processor,

responsible for modulation and demodulation of

WCDMA, GPS, and GSM signals.

Application

subsystem

The subsystem includes ARM A5 processor,

application DSP, and dedicated data mover.

The A5 processor has a clock rate of 800 MHz,

supporting function modules such as the microSD

card, EBI2, UART/USIM, I2C, GPIO, and clock

modules.

User interface

processing unit

Provides camera, PCM, broadband codec, vocoder,

RF, HKADC, LCD, SD card, USB, UART, USIM

card, SBI, GPIO, JTAG/ETM, and keypad

interfaces.

Multimedia and

game engine

The multimedia and game engine is an MPEG/JPEG

hardware engine providing Java acceleration and

MP3/MMS/MIDI/VR processing functions.

PM8029

Power supply voltage

monitoring

Lists objects being monitored, such as the external

power supply input, Li-ion battery, and charger.

Temperature

monitoring

Monitors the battery temperature.

NAND flash

memory

File system support

Stores applications and NV items. Capacity: 4 GB.

DDR1 RAM

Random access

memory

Provide storage space for running applications.

Capacity: 2 GB.

RF

subsystem

WCDMA, and

GSM/DCS

signal

transmission and

reception

AFC circuit, APC

circuit, AGC circuit

Performs the RF function of WCDMA signal

reception and transmission.

Mainly includes the RTR6285A RF chip and the

peripheral circuit.

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Subsystem

Module

Unit

Function

GPS

GPS reception

Receives and processes GPS signals.

Mainly includes the RTR6285A chip and the

peripheral circuit.

Bluetooth

interface

Bluetooth/Wi-Fi/FM

3-in-1 module

Performs baseband functions for Bluetooth, Wi-Fi

and FM signals.

Transmits and receives Bluetooth, Wi-Fi and FM

signals.

Mainly includes the Bluetooth/Wi-Fi/FM module

and its peripheral circuit.

Wi-Fi interface

Same as the

Bluetooth interface

Same as the Bluetooth interface

Oscillator and

frequency

synthesizer

Crystal oscillators

Generates highly accurate VCTCXO frequency for

the 19.2 MHz local reference clock. The RTR6285A

has a built-in local oscillator (LO) providing clock

frequency for transmitting and receiving WCDMA

and GPS signals.

Antenna

External antenna,

internal interface

component, antenna

protection

The phone uses internal antennas for wireless

communication, supporting WCDMA high and low

frequency bands.

The antennas are the main antenna, GPS antenna,

diversity antenna, Wi-Fi/Bluetooth antenna, FM

antenna (headset) and NFC antenna.

Coupler

Power coupler

Couples part of the power output from the WCDMA

power amplifier to the RTR6285A for power

monitoring.

User

interface

subsystem

UART interface

MSM7225A subsystem's UART1 interface for

Bluetooth.

USB interface

Driver, protection

circuit, output

interface component

The peripheral circuit, protection circuit and

interface connectors of the USB interface in the

MSM7225A subsystem.

It is the major data service channel for the

engineering sample, and can be used to debug and

test devices during R&D.

USIM card

interface

Power supply,

protection circuit,

USIM card holder

Mainly includes the USIM card holder and related

connection circuits.

Keypad and

backlight

Keypad driver

circuit, external

keypad, backlight

LED control circuit

Supports GPIO for keypad scanning.

Provides backlight LED. When a key is pressed, the

backlight is on.

Works in conjunction with PM8029 to provide the

keypad backlight brightness adjustment function.

Color LCD and

backlight

LCD driver, interface

mode, and backlight

control

The phone's LCD with 256K colors. The brightness

of the LCD backlight can be adjusted by users.

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Subsystem

Module

Unit

Function

Speaker

Driver mode,

connection mode,

speaker component

Plays polyphonic ringtones for incoming calls.

The maximum power of the speaker is 500 mW.

It has good frequency response for playing

20–20000 Hz ringtones. It can also play

monophonic MP3 audio files.

Receiver

Driver mode,

connection mode,

receiver component

Emits sound during a call.

Microphone

Interface circuit,

connection mode,

microphone

component

The phone has two built-in microphones to

eliminate the environmental noise.

Earphone

Earphone, headset

interface circuit,

microphone interface

circuit

The phone provides a headset jack to output music

playback audio or voice during a call. The

microphone on the headset cable can pick sound and

input it into the phone. TheU8655N supports only

the LRGM headsets.

Vibration motor

interface

Driver mode,

connection mode,

motor

When there is an incoming call, the motor can

vibrate notify the user of the call.

NFC

I2C interface control

Performs proximity sensing function.

Proximity and

illuminance

sensor

I2C interface control

Senses the intensity of environmental light for

adjusting the LCD and keypad backlight brightness.

Detects the distance between the phone and the

user's skin and turns the LCD and touchscreen panel

off when the distance is smaller than the specified

value.

Accelerometer

I2C interface control

Senses acceleration to help implement game

functions.

Battery

Li-ion battery

3.7 V/1250 mAh (the battery must be certified and

comply with relevant safety regulations).

Power

supply

subsystem

External power

supply (travel

charger)

Adapter, and

interface component

The charger meets the requirements of China,

Europe, the USA, and Australia.

Charger specifications: 90–240 V, 45–55 Hz, AC

input. The model differs with different markets.

The output voltage of the charger is 5±0.25 V.The

charger must be CE and CCC certified.

The charger's output current must be able to charge

the battery and supply power to the phone for

normal operation at the same time.

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Subsystem

Module

Unit

Function

Power

distribution

network and

power

management

function

Power distribution

network

Includes filter networks and PCB traces for the

power supply.

PM8029

enhanced

function

Battery management,

charging circuit,

charging mode, and

charging protection

Manages battery charging and discharging, provides

overcharging and over-discharging protection, and

charges the capacitor that supplies power to

maintain the real-time clock (RTC).

Board circuit power

management

(power-on/off

analysis)

Mainly controls the low-dropout (LDO) regulator

power supply to flexibly manage power supply.

Based on the service status and the requirements of

the interface power supply specifications and

power-saving analysis, the board software manages

the power supplies to the units on the board to

reduce power consumption.

RTC

The built-in RTC circuit uses a sleep clock of

32.768 kHz to provide precise time.

HKADC

Contains 8 MPP interfaces. Analog-to-digital

conversion can be implemented inside the PM8029.

TCXO driver

The PM8029 has a built-in TCXO driver providing

two analog signal output channels and two digital

signal output channels.

UVLO

Provides the Undervoltage-Lockout (UVLO)

function. When the input voltage is lower than the

threshold for a specific period of time, the phone

powers off.

Over temperature

protection

When the on-chip junction temperature exceeds

150°C, the phone powers off.

Internal driver circuit

Provides one vibration motor driver and one speaker

driver.

Interrupt

management

The built-in interrupt manager handles related

interrupt signals.

USB driver

Supports USB 2.0; does not support USB OTG.

9.2 Baseband Unit

9.2.1 Power-on Management Circuits

On the U8655N, most power supplies are provided by the power management chip PM8029.

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The PM8029 provides two types (switched-mode power supply and LDO regulators) of

programmable voltage regulators with a total of 24 output channels.

The follow table lists the voltage regulator parameters.

Table 9-2 Voltage regulator specifications

Troubleshooting Process

To troubleshoot the power-on failure, firstly check whether the I/O connector (battery

connector) is damaged. If the I/O connector (battery connector) is not damaged, use a DC

regulated power supply to supply power to the phone, and test the phone's current.

The power-on failure may be caused by any of the following conditions:

- No current

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Replace J902

N

Power-on failure:

no current

Is the battery

connector J902

normal?

Replace Q201

N

Is Q201 normal?

Y

Re-solder or replace

U201

Y

- Weak current

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YY

Reinstall the phone's

firmware. Is the problem

solved

NN

YY

Powe-on failure:

weak current

End

Is U201'output

Voltage normal

YY

Does X301 have

32.768 kHz output?

Replace U601 and reinstall

The phone's firmware. Is the

Problem solved?

YY

Replace U401

NN

Replace U201

Replace X301

End

- Excessive current

Excessive current is caused by short circuits. When excessive current occurs, to prevent

damage to components, do not connect the charger to the phone. Power-on failure due to

excessive current is usually the result of short-circuited VBAT circuit.

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NN

Test the VBAT circuit.Is it

a short circuit

YY

NN

YY

Powe-on failure:

excessive current

Check whether

VPH_PWR and

PM output are

short-circuited

Is J902 normal?

YY

Is Q201 normal?

Remove U201.Do short

circuits still exist?

YY

Replace U401

NN

Re-solder or

replace J902

Replacec Q201

Replace U201

9.2.2 Charging Management Circuits

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Troubleshooting Charging Failure

NN

Is the charger working

properly?

YY

NN

Charging failure

Replace the

charger

Is J901 poorly

soldered?

NN

Is the battery's in good

contact with the battery

connector?

Does VPH_PWR have

voltage?

YY

End

YY

Re-solder J901

Repair or replace

J902

Replace U901

Is there voltage difference

between Q201's pin 2 and

pin 3? NN Replace Q201

YY

Is the battery damaged? YY Replace the

battery

NN

9.3 RF Unit

9.3.1 RF Failure

Troubleshooting Transmission Failure

- GSM/DCS transmission failure

Before starting the following process, make sure that the USIM card and the antenna are well

connected.

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GSM/DCS transmission

failure

When the RF cable is not

inserted, are U3201's pin

1 and pin 2 connected? Check U3201

Are U3202's control signals

normal?

Check U401

Are U3501's GSM output

and DCS output

approximately 33 dBm and

30 dBm respectively?

Check U3202 and

U401

Check U3501

Y

N

Y

N

Do U3801's pin A10 and pin

A9 have output? Check U3801

N

Y

NOTE

- The following tables describe the working status of the GSM/DCS power amplifier U3501.

GSM_PA_EN

PA

H

ON

L

OFF

GSM_PA_BAND

MODE

L

GSM850/900

H

DCS1800/1900

- H: voltage higher than 1.3 V. L: voltage lower than 0.5 V.

- WCDMA transmission failure (use W2100 as an example)

Before starting the following process, make sure that the USIM card and the antenna are well

connected.

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W2100 transmission

failure

When the RF cable is not

inserted, are U3201's pin 1

and pin 2 connected? Check U3201

Are U3202's control signals

normal?

Check U401

Is the insertion loss

between U3304's pin 1 and

pin 3 approximately 1.1–1.4

dB?

Check U3202 and

U401

Check U3304

Y

N

Y

N

Is U3301's output 24 dB? Check U3301

N

Y

Is the insertion loss

between U3302's pin 2 and

pin 9 approximately 0.6 dB? Check U3302

N

Check U3801

N

Does U3801's pin A7 have

output?

NOTE

- The following tables describe the working status of the WCDMA power amplifier.

PA_ON

PA

H

ON

L

OFF

PA_R

PA_R1

MODE

L

HI Power

L

H

MI Power

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H

LO Power

- H: 1.3–1.8 V. L: < 0.5 V.

9.3.2 GPS

The GPS channel consists of filter U4102, filter U4103 and LNA U4101. GPS signals are sent

to the RTR6285A's input interface after going through the filters and LNA. The following

figure shows the circuit.

9.3.3 Wi-Fi/Bluetooth/FM Module

The U8655N uses a Wi-Fi/Bluetooth/FM 3-in-1 module (Broadcom's BCM4330).

The Bluetooth and Wi-Fi functions share one antenna and one SP3T RF switch.

The MSM7225A provides PCM and UART interfaces that are directly connected with the

Bluetooth module's PCM and UART signal output. The following table describes the signals'

definitions.

MSM7225A

Signal

Definition

GPIO_44

UART1_CTS_N

The "ready to receive" signal from the

host (the MSM7225A) to the slave (the

BCM4330).

GPIO_43

UART1_RFR_N

The "clear to send" signal sent from the

slave to the host.

GPIO_46

UART1_TX

Transmission signal

GPIO_45

UART1_RX

Reception signal

GPIO_69

AUX_PCM_DIN

PCM input

GPIO_68

AUX_PCM_DOUT

PCM output

GPIO_70

AUX_PCM_SYNC

PCM synchronization

GPIO_71

AUX_PCM_CLK

PCM clock

GPIO_107

MSM_WAKES_BT

Waking up the host

GPIO_83

BT_WAKES_MSM

Waking up the Bluetooth

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The MSM7225A provides SDIO3 interfaces that are directly connected with the Wi-Fi

module's SDIO signal output. The following table describes the signals' definitions.

MSM7225A

Signal

Function

GPIO_64

SDC2_DATA3

Data

GPIO_65

SDC2_DATA2

GPIO_66

SDC2_DATA1

GPIO_67

SDC2_DATA0

GPIO_62

SDC2_CLK

Clock

GPIO_63

SDC2_CMD

Control signal

The PM8029 provides audio input interfaces that are directly connected with the FM module's

left and right channels. The following table describes the signals' definitions.

BCM4330

Network

MSM7225A

Description

FM_RXP

FM_ANT

FM antenna (headset)

FM_RXN

-

FM_VDD2P5

SR_AVDD2P5

-

FM_AOUT1

FM_OUT_L

PM8029

LINE_IN_LP

FM OUTPUT

FM_AOUT2

FM_OUT_R

PM8029

LINE_IN_RM

FM OUTPUT

9.4 Peripheral Circuits

9.4.1 Display

The MSM7225A uses MIPI interfaces to send instructions and data to the LCD. The

U8655N's LCD uses MIPI interfaces, supporting a 60 Hz refresh rate, and requiring only one

pair of differential clock signals and one pair of differential signals. The LCD also supports

frame synchronization, using the MDP_VSYNC signals (GPIO_097) as data transmission

synchronization signals to avoid screen tearing.

- Resolution: HVGA (480 x 320 pixels)

- Color: 256K colors

The following figure shows the connections between the MSM7225A and the LCD.

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The following table describes the signal definitions.

Category

Description

Name in the Circuit

Network

MSM7225A GPIO/PM8029

MPP

Power supply

Digital power supply

input

VREG_S3

VREG_S3 (PM8029)

Analog power input

VREG_L12_2P85

VREG_L12_2P85 (PM8029)

Data

MIPI data

MIPI_DSI_LANE1_P

MIPI data

MIPI_DSI_LANE1_N

Synchronization

signal

Frame synchronization

clock

MDP_VSYNC_P

GPIO97

Clock signal

MIPI clock

MIPI_DSI_CLK_P

MIPI clock

MIPI_DSI_CLK_N

Control signal

Reset signal

LCD_RESET_N

GPIO129

Identification

signal

LCD model identification

LCD_ID0

GPIO9 (PM8029)

LCD model identification

LCD_ID1

GPIO10 (PM8029)

U8655N's LCD backlight control:

The U8655N uses a 3.5-inch LCD whose backlight is provided by six LEDs connected in

series. The backlight LEDs are controlled by the backlight driver chip TPS61160A. The

ground resistance of the driver chip pin FB is set to 10 Ω, providing up to 20 mA current to

the LEDs (duty:100%). The backlight brightness (driver output current) is controlled by the

PWM signal.

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Backlight

signals

The anode of the

backlight LED

LED_A

The anode of the backlight

LED

The cathode of the

backlight LED

LED_K

The cathode of the backlight

LED

Brightness control

signals from the LCD

PWM_OUT

Reserved

Brightness control

signals from the

phone's main chip

LCD_BL_PWM

GPIO1 (PM8029)

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Troubling Display Failure

LCD fails to display

Return the phone

to the factory

Check whether J1302 is

snapped in place. If it is not

in place, snap it again. Is the

problem solved?

End

Y

N

Reinstall the phone's

firmware. Is the problem

solved?

End

Y

N

Replace the LCD. Is the

problem solved? End

Y

N

9.4.2 Camera

The U8655N uses a 3.2-megapixel full-frame camera.

The 3.2-megapixel full-frame camera uses a 24-pin BTB connector and is controlled by the

I2C bus. The data is transmitted in MIPI mode.

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Signal Name

Voltage

Description

CAM_VIO

VREG_S3

1.8

Controlled by the power

supply switch.

CAM_VIO

VREG_S3

1.8

Controlled by the power

supply switch.

VREG_CAM_2P85

VREG_L17(PM8029)

2.85

Power supply to the

camera autofocus motor

CAM_AVDD

VREG_L17(PM8029)

2.85

CAMIF_MCLK

GPIO_015(MSM7225A)

1.8

Camera reference clock

MCAMIF_SHDN

GPIO_119(MSM7225A)

1.8

Camera shutdown signal

CAM_VCM_PD_N

GPIO_07(MSM7225A)

1.8

Camera autofocus motor

control signal

I2C0_SCL

GPIO_060(MSM7225A)

1.8

I2C control signal

I2C0_SDA

GPIO_061(MSM7225A)

1.8

MCAMIF_RESET

GPIO_049(MSM7225A)

1.8

Reset signal

MCAMIF_ID

GPIO_9(MSM7225A)

1.8

Module supplier

identification

MIPI_CSI2_CLK_P

MIPI clock

MIPI_CSI2_CLK_N

MIPI clock

MIPI_CSI2_LANE1_P

Data communication

signal

MIPI_CSI2_LANE1_N

Data communication

signal

MIPI_CSI2_LANE0_P

Data communication

signal

MIPI_CSI2_LANE0_N

Data communication

signal

NOTE

The camera interface circuit is designed for compatibility with multiple types of cameras. The U8655N

uses a 3.2-megapixel full-frame camera, so the CAM_VCM_PD_N and VREG_CAM_2P85 lines are

not used.

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Troubleshooting Camera Failure

Failure to take photos or

record video using the

camera

Replace the

camera. Is the

problem solved? End

Is J1001 poorly soldered or

are its contacts defective?

Return the phone

to the factory

Re-solder or replace

J1001

Y

N

Y

Reinstall the phone's

firmware. Is the

problem solved?

End

Y

N

9.4.3 USB

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Troubleshooting USB Connection Failure

USB connection failure

Reinstall the

phone's firmware.

Is the problem

solved?

End

Is the 5-pin mini USB

connector poorly soldered?

Return the phone

to the factory

Re-solder the USB

connector

Y

N

Y

Use a normal USB

cable. Is the problem

solved? End

Y

N

9.4.4 Headset Jack

The headset jack is a 3.5-mm headset jack. When the headset jack has no headset inserted, the

headset jack's pin 3 and pin 4 are open, and the headset detection voltage is at high level.

After a headset is inserted, pin 3 and pin 4 are closed, and the headset detection voltage is at

low level, indicating the insertion of a headset. The HS_DETECT (GPIO86) pin is used to

detect the headset insertion.

The HSED_MICBIAS (PM8029/HSED_BIAS1) supplies power to the headset microphone.

The HSED_HSKEY_ADC (PM8029 MPP5) is used to detect the headset button press.

NOTE

The U8655N supports only LRGM headsets, and does not support LRMG headsets.

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- No sound comes from the headset during a call

After a call is established, no

sound can be heard from the

headset

Is a headset icon

displayed on the

screen?

Replace the

headset jack

Replace the headset. Is the

problem solved?

Return the phone

to the factory

End

Y

N

Is the in-call volume

set to a normal level? End

N

Y

- The headset button cannot be used to answer a call

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The headset button cannot be

used to answer a call

Is the voltage on J1101's

pin 4 at low level after the

headset is inserted?

Return the phone

to the factory

Check that J1101 is

properly soldered.

N

Replace the headset.

Is the problem solv ed? End

Y

N

9.4.5 Keys

The U8655N has six keys, three of which are the Menu, Home and Back keys on the

touchscreen panel.

The MSM7225A's GPIO_42 and GPIO_41 pins are connected to the volume up and down

keys. The side key FPC is connected to the PCBA via the ZIF connector J1605.

The Power key press is detected by the PM8029's KPD_PWR_ON pin. The Power key FPC is

connected to the PCBA using press-fit contacts.

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Troubleshooting Key Failure

Key failure

Are the FPC and ZIF

connector connected

properly? Re-connect them

Return the phone

to the factory

Y

N

Is the keypad on the

FPC in good contact

with the dome sheet?

Clean the

keypad and the

dome sheet

N

Y

9.4.6 Status Indicator and Touch Key Backlight Circuits

The U8655N's status indicator (tricolor indicator) provides red, green and blue light sources

that are driven by the PM8029's three LED drivers.

Light

Source

Driver Pin (PM8029)

Description

Red

LED_RED_DRV_N (MPP3)

Adjusted using electric current

Green

LED_GREEN_DRV_N (MPP5)

Adjusted using electric current

Blue

LED_BLUE_DRV_N (MPP8)

Adjusted using electric current

The KYPD_DRV_N (PM8029) is used to adjust the brightness of the keypad's backlight, and

VPH_PWR is used to supply power to the backlight LEDs. The keypad backlight is provided

by two white LEDs. The light from the LEDs are transmitted to the key area using a light

guide film.

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Keypad Backlight Driver

VPH_PWR

Power supply

Backlight power supply

KPD_DRV_N

Backlight driver pin

When this pin's voltage is at low

level, the two backlight LEDs

turns on.

9.4.7 Battery Connector

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9.4.8 Accelerometer

Component

Network

MSM7225A Pin

Description

SCL

I2C1_SCL

GPIO_131

I2C bus

SDA

I2C1_SDA

GPIO_132

INT1

MEMS_INT1

GPIO_28

Accelerometer interrupt

signal

INT2

MEMS_INT2

GPIO_111

Accelerometer interrupt

signal (sleep)

9.4.9 Proximity and Illuminance Sensor

The U8655N has a proximity and illuminance sensor. The following figure shows the sensor

circuit.

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Component Pin

Network

MSM7225A-0 Pin

Description

SCL

I2C1_SCL

GPIO_131

I2C bus

SDA

I2C1_SDA

GPIO_132

INT

PRO_INT

GPIO_17

3-in-1 interrupt signal

Functions

- Detect the intensity of environmental light.

- Detect the proximity of objects.

The phone's display does not

turn off when near the user's

ear during a call

Is U1207 poorly soldered

or dirty? Re-solder, clean

or replace U1207

Reinstall the phone's

firmware. Is the problem

solved?

Return the phone

to the factory

End

Y

N

Y

Is the touchscreen panel's

illuminance sensor hole dirty

or blocked?

Clean the hole

Y

N

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9.4.10 Vibration Motor

The motor driver current is controlled by PM VIB_DRV_N.

Troubleshooting Vibration Failure

Vibration failure

Is the voltage on

VIB_DRV_N equal to

the battery voltage? Replace D902

Replace the motor. Is the

problem solved?

Return the phone

to the factory

End

Y

N

Y

Reinstall the phone's

firmware. Is the

problem solved?

End

Y

N

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9.4.11 Receiver

The receiver receives differential earphone output from the MSM chip. The following figure

shows the circuit.

The MSM chip's EARI output signal is connected to the receiver. Bypass capacitors are added

to the signal traces. The circuit shown in the previous figure is designed for compatibility.

L1508, L1510 and U1501 are reserved for the HAC function and are not soldered on the

U8655N. D1503 and D1504 are the ESD protection components on the receiver.

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Troubleshooting the Failure that No Sound Can Be Heard During a Call

No sound is heard

during a call

Replace the

receiver. Is the

problem solved? End

Does the phone mistakenly

detect the insertion of a

headset?

Return the phone

to the factory

Replace the

headset connector

Y

N

Y

Is the in-call volume

set to a normal level? End

N

Y

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9.4.12 Microphone

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Troubleshooting the Failure that No Sound Can Be Heard by the Other Party

During a Call

No sound can be heard by

the other party during a call

Replace the

microphone. Is the

problem solved? End

Is the MIC_BIAS voltage

equal to 1.8 V?

Return the phone

to the factory

Check U201

N

Y

Reinstall the phone's

firmware. Is the

problem solved? End

Y

N

9.4.13 Touchscreen Panel

The U8655N's 3.5-inch capacitive touchscreen panel has a touch key area containing three

touch keys. The backlight LEDs for the three touch keys are located on the PCBA. A light

guide film is used to guide light from the LEDs to the touch key area.

The following table describes the interfaces between the touchscreen panel, MSM7225A and

PM8029.

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Touchscreen Panel

Interface

Description

VDD_2V8_TP

VREG_L12_2P85 (PM8029)

Touchscreen panel analog power supply,

2.85 V

VREG_S3

VREG_S3 (PM8029)

Touchscreen panel digital power supply and

I/O connector power supply, 1.8 V

TOUCH_INT

GPIO_82 (MSM7225A)

Touchscreen panel interrupt signal

I2C1_SCL

GPIO_131 (MSM7225A)

Touchscreen panel's I2C clock

I2C1_SDA

GPIO_132 (MSM7225A)

Touchscreen panel's I2C data

TOUCH_RST_N

GPIO_96 (MSM7225A)

Touchscreen panel reset signal

9.4.14 SIM Card

The MSM7225A is not compatible with the SIM card interface. The PM8029's MPP pins are

used to convert voltage levels of the signals for communication between the MSM7225A and

the SIM card.

The voltage of VREG_L16_UIM1 can be set to 1.5–3.05 V. The USIM interface's operating

voltage is usually 1.8 V or 3.0 V. The following table describes the voltage level conversion

interface of the PM8029.

Signal for Interfacing

with the MSM

Voltage Level

Signal for Interfacing

with the USIM Card

Voltage Level

VREG_S3

UIM1_RESET

VREG_L16_UIM1

(configured by the

phone's firmware)

UIM1_MSM_CLK

UIM1_CLK

UIM1_MSM_DATA

UIM1_DATA

NOTE

Considering that SIM card operations are frequent, transient-voltage-suppression (TVS) diodes are

added to the circuit to provide ESD and surge protection.

USIM card circuit

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9.4.15 microSD Card

The microSD card connector's SD_DETECT pin is used to detect the insertion of a microSD

card. When a microSD card is inserted, the pin is grounded and its voltage is at low level.

When no microSD is inserted, its voltage is at high level. The U1402 is an EMI and ESD

protection component for the microSD card.

The following figure shows the circuit.

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9.4.16 NFC

U8655N supports NFC module function, and uses NFC control chip of NXP to receive and

process signal. when use NFC function normally, the battery cover must be covered because

of built-in antenna. the signal NFC_VEN_MOS which is the reset signal of NFC module is

controlled by NFC_VEN signal, this module uses a clock of 19.2MHz to ensure module work

properly.

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Troubleshooting the Failure of NFC swiping

YY

Update the phone's software,

Is the problem solved?

NN

Swiping card

failure

End

Is the antenna in

good contact with

metal dome?

YY

Is power output

Voltage normal?

YY

Return to factory

Replace battery

covere with antenna

Re-solder U4401

Signal name

Description

Voltage or Waveform

NFC_VEN_MOS

NFC chip reset signal

The same voltage of battery

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Maintenance Manual

9 Principles and Failure Analysis

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Signal name

Description

Voltage or Waveform

NFC_VEN

The reset signal from CPU

1.8V

NFC_TX1

Contactless Transmitter output1

-

NFC_TX2

Contactless Transmitter output2

-

VBAT

Battery power

Battery voltage 3.6V-4.2V

VREG_S3

power

1.8V

TCXO_OUT_NFC

Clock signal

19.2MHz

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Maintenance Manual

10 Solder Points on the PCB and BGA Chip

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10 Solder Points on the PCB and BGA

Chip

Red (R: 255, G: 0, B: 0) : Vacant point

Green (R: 0, G: 255, B: 0) : Ground point

Blue (R: 0, G: 0, B: 255) : Solder point

Magnified views of sections:

PM section

MSM7225A+NAND MCP section

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Maintenance Manual

10 Solder Points on the PCB and BGA Chip

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Wi-Fi/Bluetooth/FM section

RTR8285A section

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Maintenance Manual

10 Solder Points on the PCB and BGA Chip

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Complete PCB view:

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Maintenance Manual

10 Solder Points on the PCB and BGA Chip

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10 Solder Points on the PCB and BGA Chip

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U8655

Maintenance Manual

11 Functional Tests

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11 Functional Tests

11.1 MMI Test

On the Home, enter *#*#2846579#*#* to enter the MMI test mode. Press the Volume– key to

start a test. Touch the Menu key on the touchscreen panel to skip the current test and go to the

next step. Touch the Back key to return to the previous test.

NOTE

- When no battery is installed or the battery voltage is low, the phone will indicate that the battery is

low and the MMI test cannot be started.

- During a test, if you touch the Menu key on the touchscreen panel, the test will be skipped and

marked as a failed test.

No.

Category

Item

Test Method

1

SD card test

microSD card test

Automatically test the microSD card functions. If a

microSD card is found and is available, the test passes.

Otherwise, the test fails.

If this test passes, the next test automatically starts.

2

SIM card test

Automatically test whether the SIM card can be

recognized. If the SIM card cannot be recognized, a

message will be displayed, indicating that this test fails.

If this test passes, the next test automatically starts.

3

Battery test

Automatically test whether the battery is in place and

whether its power is sufficient. If this test fails, a message

will be displayed.

If this test passes, the next test automatically starts.

4

Keypad test

Keys

Press or touch all the keys.

When a key is pressed or touched, the color of the

corresponding key displayed on the screen will change

(from white to blue, or from blue to white). After all keys

are tested, press the Volume– key to start the next test.

5

LCD test

White screen

The LCD displays a white screen.

Press the Volume– key to start the next test.

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No.

Category

Item

Test Method

Black screen

The LCD displays a black screen.

Press the Volume– key to start the next test.

Red and blue bars

The LCD displays red and blue bars.

Press the Volume– key to start the next test.

6

LCD backlight

and status

indicator test

LCD backlight and

status indicator

If the LCD backlight repeatedly turns on and off, the

LCD backlight is normal. The status indicator is normal if

its color repeatedly changes in the sequence of red, green

and blue.

Press the Volume– key to start the next test.

7

Keypad LED

test

Keypad backlight LEDs

If the keypad backlight repeatedly turns on and off, the

backlight LEDs are normal.

Press the Volume– key to start the next test.

8

Camera test

Automatically test the camera. The phone's camera is

turned on, and the LCD displays the preview. Check the

image quality visually and test the camera's response

speed to determine the camera's performance.

Press the Volume– key to start the next test.

9

Touch screen

test

Touch screen panel

There are three vertical gridlines which are composed of

a group of squares, one is in middle, the other are on

edge, Place your figure on the touch screen panel, and

slide your figure sweep each square along the gridline.

The areas near the route that your figure passes should

turn red. it will fail if the finger sweeps outside of these

squares.

Press the Volume– key to start the next test.

10

Approach test

The proximity and

illuminance sensor's

proximity detection

function

Place the light shielding plate approximately 4 mm above

the light hole. If a phone icon is displayed nearby the

portrait, the function is normal.

If this test passes, the next test automatically starts.

11

Environmental

light test

The proximity and

illuminance sensor's

function to sense

environmental light

Check whether the environmental light sensing data is

detected: Use your hand to block the light hole, the light

sensing number will decrease approximately 10 if the

illuminance sensor functions properly.

If this test passes, the next test automatically starts.

12

Vibration test

Vibration motor

The motor will vibrate intermittently.

Check whether the vibration (including the vibration

sound) is normal.

Press the Volume– key to start the next test.

13

Speaker test

Automatically test the speaker. (Do not insert the

headset.) If the speaker emits sound during the test, it is

normal.

Press the Volume– key to start the next test.

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No.

Category

Item

Test Method

14

Mobile phone

mic loopback

test

Main microphone

(located near the USB

port)

Do not insert the headset. Touch the Record button.

Speak to the main microphone, and then touch the Play

button. If the main microphone is normal, you can hear

the voice recording from the receiver.

Press the Volume– key to start the next test.

15

Mobile phone

loopback test

Secondary microphone

(located above the

camera at the phone's

rear)

Do not insert the headset. Touch the Record button.

Speak to the secondary microphone, and then touch the

Play button. If the secondary microphone is normal, you

can hear the voice recording from the receiver.

Press the Volume– key to start the next test.

16

Dual MIC test

Main and secondary

microphones

Do not insert the headset. Touch the Record button.

Speak to the phone as you do during a call, and then

touch the Play button. If the main and secondary

microphones are normal, you can hear the voice

recording from the receiver.

Press the Volume– key to start the next test.

17

Mobile phone

Headset

loopback test

Headset

Insert the headset. Touch the Record button. Speak to the

headset microphone, and then touch the Play button. If

the headset is normal, you can hear the voice recording

from the headset's earphones.

Keep the headset inserted. Press the Volume– key to start

the next test.

18

FM test

The testing software will detect whether a headset is

inserted. If no headset is inserted, a message requesting a

headset to be inserted will be displayed. After a headset is

inserted, the phone will search for and play an FM

channel. Three frequencies (88 MHz, 98 MHz and 107

MHz) will be tested. The 88 MHZ frequency will be

tested first. To test the next frequency, touch Next

Channel.

Remove the headset. Press the Volume– key to start the

next test.

19

Headset Wire

control test

Headset button test

Insert the headset. The IN icon will turn green.

Press the headset button, and the round dot will become

smaller. Remove the headset, and the OUT icon will turn

green.

Press the Volume– key to start the next test.

20

Bluetooth test

Automatically test the Bluetooth functions.

During the test, the phone will search for Bluetooth

devices, and display the MAC addresses of the Bluetooth

devices that have been found. (Note: This test requires

another device with Bluetooth enabled.)

Press the Volume– key to start the next test.

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No.

Category

Item

Test Method

21

Gravity sensor

test

Accelerometer

The LCD displays the current acceleration in the X, Y

and Z axes. Place the phone in a position where the

angles between the X, Y and Z axes are 45°. If the

acceleration in the X, Y and Z axes is equal to each other,

the phone passes this test.

If this test passes, the next test automatically starts.

22

WiFi test

Wi-Fi test

Automatically test the Wi-Fi functions.

During the test, the phone will search for nearby hotspots,

and display the MAC addresses of the hotspots that have

been found. (Note: This test requires an active hotspot in

the testing environment.)

Press the Volume– key to start the next test.

23

Display test

Displaying test results

Display the MMI test results.

Failed test items will be listed.

11.2 Voice Call Test

1. Install a UIM card and a battery on the phone.

2. Press the Power key to power the phone on.

3. Check whether the signal strength displayed on the LCD is normal (given that the

network is normal).

4. Make a call to a fixed-line phone, and check the voice quality during the call.

5. If no problems are found during the test, finish the voice call test. If any problems are

found, troubleshoot the phone or send it to an advanced service site for repair.

Huawei Release Notes F Tanjim Qmobile Call Centre Singer Y200 U8655 1. 51053288 U8655N(MTC965) Maintenance Manual V1.0

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