Lenovo A850 Service Manual

Service Manual of

Lenovo A850 Mobile

Phone

LENOVO

Repair Manual of Lenovo S920 Mobile Phone

Document name Service Manual of Lenovo A850Mobile Phone
Version: V100
Date: Sept. 19, 2013
Document No.:
Status:

Preface

This manual is intended for online repair guidance and after-sale repair guidance of

Lenovo A750 mobile phone produced by the Company

The content of this manual will be upgraded according to the needs of technology

development.

Copyright

The copyright of this manual belongs to Lenovo Mobile; anyone who reproduces this

manual without written consent of the Company shall bear legal responsibility.

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Repair Manual of Lenovo S920 Mobile Phone

Content

1. APPEARANCE .............................................................................................................................. 6

2. LAYOUT OF MAIN BOARD ........................................................................................................ 7

3. BASEBAND ................................................................................................................................... 9

3.1 LCD DISPLAY ......................................................................................................................... 10

3.1.1 No display on screen after power-on ................................................................................. 10

3.1.2 LCD backlight without lighting ......................................................................................... 11

3.2 CAMERA DEFECTS ................................................................................................................... 12

3.2.1 Rear camera defects .......................................................................................................... 12

3.2.2 Front camera defects ......................................................................................................... 13

3.3 RING AND VIBRATION .............................................................................................................. 14

3.3.1 No vibration ....................................................................................................................... 14

3.3.2 No ring ............................................................................................................................... 15

3.4 CHARGING .............................................................................................................................. 16

3.4.1 No charging display after plugging the charger in ............................................................ 16

3.4.2 Charging shown but not full charging ................................................................................ 17

3.5 KEYBOARD AND KEYBOARD BACKLIGHT ................................................................................ 18

3.5.1 Abnormal operation of side keys ................................. Ошибка! Закладка не определена.

3.5.2 Abnormal operation of CTP keyboard ............................................................................... 18

3.5.3 Abnormal Display of RGB LED ..................................... Ошибка! Закладка не определена.

3.6 CALLING ................................................................................................................................. 19

3.6.1 No voice heard from the other side during the call ............................................................ 19

3.6.2 No voice heard from your side during the call ................................................................... 20

3.7 POWER-ON FAILURE ................................................................................................................ 21

3.8 LCD ON WHEN CLOSE TO THE EAR DURING THE CALL; LCD OFF WHEN AWAY FROM THE EAR. 22

4. RADIO FREQUENCY (RF) ................................ ОШИБКА! ЗАКЛАДКА НЕ ОПРЕДЕЛЕНА.

4.1 SOFTWARE DOWNLOAD FAILURE .................................... ОШИБКА! ЗАКЛАДКА НЕ ОПРЕДЕЛЕНА.

4.2 PRODUCTION CALIBRATION ............................................. ОШИБКА! ЗАКЛАДКА НЕ ОПРЕДЕЛЕНА.

4.2.1 AFC calibration.............................................................. Ошибка! Закладка не определена.

4.2.2 AGC ................................................................................ Ошибка! Закладка не определена.

4.2.3 APC ................................................................................ Ошибка! Закладка не определена.

4.3 FAULT IN COMPLETE SET TEST/ REWORK .......................... ОШИБКА! ЗАКЛАДКА НЕ ОПРЕДЕЛЕНА.

4.3.1 Switch spectrum & PVT template with excessive standard ................. Ошибка! Закладка не

определена.

4.3.2 High Frequency Error .................................................... Ошибка! Закладка не определена.

4.3.3 High Phase Error ........................................................... Ошибка! Закладка не определена.

4.3.4 Power output problems .................................................. Ошибка! Закладка не определена.

4.4 WCDMA FORECAST........................................................ ОШИБКА! ЗАКЛАДКА НЕ ОПРЕДЕЛЕНА.

4.4.1 RSSI_Cal ........................................................................ Ошибка! Закладка не определена.

4.4.2 TPC_Cal ......................................................................... Ошибка! Закладка не определена.

4.5 WCDMA COMPREHENSIVE TEST ..................................... ОШИБКА! ЗАКЛАДКА НЕ ОПРЕДЕЛЕНА.

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Repair Manual of Lenovo S920 Mobile Phone

4.5.1 ACLR or SEM ................................................................. Ошибка! Закладка не определена.

4.5.2 ILPC comprehensive test abnormal ............................... Ошибка! Закладка не определена.

4.5.3 FrequencyErr ................................................................. Ошибка! Закладка не определена.

5. STRUCTURE ASSEMBLY ........................................................................................................ 23

5.1 ASSEMBLY PROCESS SEQUENCE OF LENOVO S820 MAIN BODY .................ОШИБКА! ЗАКЛАДКА НЕ

ОПРЕДЕЛЕНА.

5.2 PRECAUTIONS IN LENOVO S820 MAIN BODY ASSEMBLY .. ОШИБКА! ЗАКЛАДКА НЕ ОПРЕДЕЛЕНА.

5.3 PRECAUTIONS IN DISASSEMBLY OF LENOVO S820 MAIN BODY FOR REPAIRING ................. ОШИБКА!

ЗАКЛАДКА НЕ ОПРЕДЕЛЕНА.

4

Version

No.

Prepared by/

Modified by

Prepared/

Modified

on

Reason for

change

Main changes

1. Appearance

Repair Manual of Lenovo S920 Mobile Phone

2. Layout of main board

Front of main board:

7

Repair Manual of Lenovo S920 Mobile Phone

Back of main board:

8

Repair Manual of Lenovo S920 Mobile Phone

3. Baseband

Block diagram of hardware system

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Repair Manual of Lenovo S920 Mobile Phone

White screen or blank screen without display; backlight

with lighting

Check whether the EMI device E1601,E1602,
E1603 of LCD circuit on main board is welded
incompletely; re-weld EMI device

OK

Check whether there is cold solder joint on other
device around LCD and on LCD connector.

Check whether the connection of LCD FPC is
good and re-assembled FPC phone is normal
N

N

Y

OK

Y

Check whether the display is normal after
replacing LCD,

N

OK

Y

LCD display

3.1.1 No display on screen after power-on

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Repair Manual of Lenovo S920 Mobile Phone

Check whether there are voltages more than
20V between both ends of C1606 when LCD
is lit.

OK

If the backlight circuit is
normal, it is the problem
of LCD

Check the welding condition of U1601
and peripheral devices, including
L1601, D1601, C1606,C1604，
R1606,R1608，R1609

Y N Y

Y

OK

Check whether the connection of FPC on
LCD module and connector on main board is
good and whether the LCD backlight is
normal after reconnection

N

Re-verify whether the LCD backlight is
normal after replacing LCD.

OK

Y

N

LCD backlight without lighting

3.1.2 LCD backlight without lighting

11