texet TM-D105 User manual

TM-D105 Service manual
Table of contents
1. Introduction
1.1 Purpose
1.2 For your safety
2. Tesing mode
3. Repair
3.1 Basic knowledge for mobile phone repair
3.1.1 Classification for failure causes
3.1.2 Failure classification
3.1.3 Repair procedures
3.1.4 Basic repair environment
3.2 Level 0 Repair
3.3 Level 1 Repair
3.4 Level 2 Repair
3.5 Check out after repair
4. Level 3 Repair
4.1 The Block Diagram Of Logic
4.2 RF Block Diagram
4.3 Repair procedure

1. Introduction
1.1 Purpose
This service manual introduces some relevant information about ST009 phone,
it is used by engineers who is familiar with using the similar machine type,
which provides certain instruction function for after-service and manufacturing
repair.
1.2 For your safety
1.2.1 For your operational safety, all the machines have to be earthing
according to the instruction on the manual during repair.
1.2.2 Please do not use mobile phone near to the electric sparks or
somewhere may exploding.
1.2.3 Mobile phone may interfere with other delicate machines, so you
have to power off your mobile phone when you approach to the
places where No Mobile Phone signals posted, to prevent it from
shooting any signals.
2. Testing Mode
Press “*#66*#” to enter into the engineering mode after mobile phone start up, mainly test
and confirm on some functions, main function table is as following:
Code Option Description
*#66*#
1.Version Display software version
2: Resource BIN
3: Echo Loop Microphone test
4.Keypad Test every keypad function
5.Vibrator Test phone vibrator
6.Loud Spk Free hand
7.Ring Ring test
8. LED LED test
9. LCD LCD test
10.LCD Contrast Main LCD contrast test
11. Receiver Receiver test
12.ADC ADC calibration
13.Charger Charger current
14.Headset Test headset
15.RTC Alarm clock
16.MTBF
17.UART
18. Memory Card Memory Card test
19. FM Radio Test FM
20 Flashlight /

3. Repair
3.1 Basic knowledge for mobile phone repair
3.1.1 Classification for failure causes
(1) Phone setting incorrect
Strictly speaking, the incorrect phone setting is not belonged to failure. For
instance “no response when incoming call” could be caused by call forwarding
setting; call out limited could be caused by call barring setting; no voice sound
could be caused by turn the voice volume control off;… etc. These are the most
common problems when using the phone first time. That’s why the repairer
have to know many kinds GSM phone of operating methods well.
(2) Operating failure
In general, this failure causes by user’s incorrect operating and settings are in
the following list.
(2.1) Mechanical damaged: Failure induced by operating handset hardly or
incorrectly may cause component breakdown, handset shape changed and
IC soldering broken. Besides, antenna broken, housing and lens broken,
handset immersed in water, etc.These are belonged to this item.
(2.2) Operating incorrectly: For instance, pressing the keypad by fingernail when
using the phone and cause the print fall off；using poor or unsuitable
charger could damage the charging circuit even induce an accident；
incorrect phone setting causes handset response abnormal; typing error
pin code causes SIM lock .
(2.3) Incorrect maintainence: mobile phone is a very delicate electronic products
of high-tech, which should be used and storaged in dry, fitful temperature
environment.
3.1.2 Failure classification
(1) It can be classified into three categories without disassembly handset
(1.1) No function, including no power on；when supply DC power supply as
battery while the handset has no any response.
(1.2) Phone can’t be fully power on. Handset still consumes current when power
on , but no any power on message showing, keypad backlight, LCD
backlight, vibrator and ring tone etc.
(1.3) Power on normally, but some functions failure. For example, key failure,
abnormal display(error messages, black or white display and wrong
character on LCD) no voice, no dial up function, part functions lost.
(2) Classify into three categories after disassembly to check its PCB
(2.1) Power management failure
(2.2) Logical part failure(including 26MHz system clock, software)
(2.3) Transceiver failure
These three failures may be dependence to each other’s. For example, software
failure could cause power management IC none working, transceiver PLL unlock,
RF power lose control, synchronization fail; beside, HW 26 MHz are for system
and software operation, this impacts the accuracy of software operation .

3.1.3 Repair procedures
Please follow up the procedures as the following list when repairer gets the failure
phone.
(1) Find out the root cause before starting repair
Check with user what failure phenomenon, how it happen firstly before start to repair
it. Check the outlook of the phone whether there was any broken. Besides, check the
phone whether it is a secondhand or had been repaired already; and how many
years have been used. This information is helpful for a good experience repairer to
do failure analysis and judgment and it can help to improve the quality and efficiency
of repair service.
(2) Failure record
The category of failure could be no power on, immersed in water, throw down, no
display, etc over ten types. But each failure cause could be quite different. Failure
record is for recording the failure phenomenon and repair purpose and as a contract
for user and repairer. Besides, it must to check whether there is any other failure
exists to avoid an argument from customer after service.
(3)Recording repair phone model, IMEI
Every phone has it’s own IMEI code and do not mix with others.
(4)Get to know the operation procedures for the phones to be repaired
If the phone repair engineer could not setup or use mobile phone, its just like the
motor repair engineer can not drive a car. So, it’s very necessary to be familiar with
the operational instruction.
(5)Repair phone in a working house
You don’t repair a phone on the spot of customers or users, if you are not very
confident about it. But you can disassemble it to observe to avoid the nervous mood,
which will cause operation failure to bring up new malfunctions.
(6) Simple to complex, easy to difficult
This is the basic rule when do the failure checking unless the phenomenon is very
special and easily to judge the root cause.
(7) Check out the SW version
Check the SW version, to see whether this version all have the same problem, it can
help to conclude the problem. If you upgrade your SW, you’ve got to check out your
SW again to confirm that your SW has already upgraded.
(8) Check the audio, SIM interface, ring tone, keypad, display, microphone, receiver and
vibrator functions whether they are ok or not.
(9) Assemble or disassemble the phone according to the right order
Assemble or disassemble the phone could protect the phone, and improve the repair
efficiency. Different phones have different assembly or disassembly procedures
according to the phone model.
(10) Keep on repair diary
Keep on repair diary could help you to accumulate experiences continuously in the
incoming repair future, at the same time it could trace back the phone’s repair history.

3.1.4 Basic repair environment
(1) Basic environment
First of all, you need a silent environment to repair mobile phone, do not repair in the
noisy places; environment should be simple, bright, in mid-huminity and mild
temperature, no powder or smog exist.
(2) Working platform’s decoration
Spread a insulating table cloth guarding against static electricity on the working table;
prepare a component shelf which has many small drawer to storage the relevant
accessories and components during disassembly, get the working desk lamp and
magnifier available.
(3) Matters needing attention
Please touch the earth wire every time you disassemble the mobile phone, to get rid of
the static electricity of body. Take care of your wearing, don’t wear any chemical fabric
clothes while repairing mobile phone.
3.2 Level 0 Repair
Level 0 repair do not make any disassembly actions on mobile phone, just need to
confirm on deficient point and deliver the deficient report, and to make replacement
on the deficient mobile phone.
3.3 Level 1 Repair
Mainly not to dismantle the screw on the phone.
3.3.1 Replace the battery: check out whether the battery voltage is below 3.3V,
which makes mobile phone not to start up.
3.3.2 SW upgrade: renew the SW version using Fast Load.
3.3.3 Regain the default setup: return the phone back to default setup.
3.3.4 Accessory problems: replace earphone, battery or charger etc.
3.3.5 Operational instruction: you may try to solve the problem according to the User
Manual.

3.4 Level 2 Repair
Mainly on mobile phones whose screw dismantled, but the separating cover
not dismantled.
3.4.1 Replace the phone cover or components on the cover(you do not need to use
hot-iron or hot-wind gun):
Including keyboard pasting paper(Metal Done), LCD soft seal, LCD module front
panel, receiver, vibrating motor, silica gel key etc.
3.4.2 Simple manual testing order:
Use the simple manual testing order to check out whether the SW version, vibrator,
LCD module, MIC are in good condition.
3.4.3 Replace the inbuilt antenna:
The inbuilt antenna is hot-melted on rear houding, dismantle the rear houding and
replace the rear houding with the hot-melted antenna.
3.5 Check out after repair
3.5.1 After repair you need to pay attention on the following things:
(1) Wether there is any scratch on front and back cover or Len (phones need to be
confirmed with customers on the delivery, to see wether there is any scratch on
the phone’s appearance), Lens and LCD should have no finger print.
(2) Check wether the handset is well assembled with front and back cover, there
should not be any obvious chink or crack.
(3) Check up all the keys on the phone, to make sure there is no wrong feeling
phenomenon.
(4) Check by eye to see there is no deformity on battery bomb splinter.
(5) Start up to check wether the LCD is slanting while backlight is light on.
(6) Please tear off the lable on the original back cover( including IMEI Label), and
paste it to the new back cover. Avoid damaging the lable while tearing, you may
heat the lable by wind gun(Note: heating time should not be too long to damage
the back cover.
3.5.2 Make function test and checking after repairing on the PCB.
(1) Whole handset checking:
Observe the whole mobile phone, you can confirm the calling functions and voice quality
by dialing or receiving phonecall, and to observe the vibrating bell’s quality; also, you can
identify phone’s relevant functions to be normal or abnormal by manual testing function.
(2) SW Test
Make SW test on SW, particularly on the phones handled on FLASHROM, EEPROM, you
can test on phone’s storaging functions by dialing numbers; confirm that there is no fault
on function table by using function table, and to further testify wether the logic part
operating normally by charging phone, and you can also check the battery power function
to re-check wether logic part works normally.

4. Level 3 Repair
4.1 The Block Diagram of Logic part
4.2 RF Block Diagram
Note: ST009 support GSM850/900/DCS1800/PCS1900 four frequency channels in
the front module, This product’s front module gathers PA and Antenna Switch into one
chip, which makes it different from the other mobile phone, also the Tranceiver part and
base belt part gather into one chip.
As showed on the diagram, the wireless signal is transferred to receiving end from
antenna end, then enter PA module, pass Antenna Switch to select frequency chennal
first, then pass SAW Filter, hight-frequency signal enter into E-GOLDradio chip directly,
passing LNA low-voice amplifier to amplify the received signal, then to mix frequency
channel with the base vibrating frequency channel in base vibrating module(TRANCE is
Zero intermediate frequency), wave and moldulation cause I,Q differential signal, then to
be balanced, speech sounds and channel decode, and finally pass through DAC digital
mold transferring output analogy voice signal.
On the sending end, voice signal input by MIC shifts into digital signal through ADC, to
make the voice and channel code, GMSK modulation and frequency compounding, at
last amplified by PA and then output by Antenna.

4.3 Repair procedure
Symptom 1
Cannot power on
Test condition : 3.8V
(1) Short or large current when start up
Check Battery power whether it has any component broken; short or dust in
side the power on block.
Replace the bad component.
(2) Plug charger in.
If it power on automatically after charger plug in, pls check power on block
and key pad whether it has any component broken; short or dust in side.
Replace the bad component.
(3) No current when power on
Mainly check Battery and its connecting area, whether it has any component
broken; short-circuit or dust in side the power on block.
Replace the bad component.
(4) Power-on electrical current too weak
Upgrade SW, if the SW can not be updated, please especially check whether
32．768k is working now, is 26MHz vibrating or not; if they are all in normal
condition, just check whether CPU and Flash are connected well.
Replace the bad component.

Symptom 2
LCD no display or partially
Check LCM display block and Hot bar area, whether it has any component broken,
short-circuit, solering failure or foreign body inside.
Replace the bad component.
Symptom 3
No incoming call ring tone or weakness
Check the Speaker block , whether it has any component broken, short-circuit or
foreign body inside.
Replace the bad component.
Symptom 4
No sidetone or no voice from caller or weakness
Check the Rceiver block, whether it has any component broken, short-circuit,
solering failure or foreign body inside.
Replace the bad component.
Symptom 5
The listener can’t hear voice
Check the Microphone block, whether it has any component broken, short-circuit,
solering failure or foreign body inside.
Replace the bad component.
Symptom 6
No charging function
Check the Charge block, whether it has any component broken, short-circuit,
foreign body inside.
Replace the bad component.
Symptom 7
Vibration no function or noisily
Check the Vibrator block, whether it has any component broken, short-circuit,
foreign body inside.
Replace the bad component.
Symptom 8
Keypad function failure
Check the Keypad scan block, whether it has any component broken, short-circuit,
foreign body inside.
Replace the bad component.
Symptom 9
No SIM display after SIM card plugged in
Check SIM card block, whether it has any component broken, short-circuit, foreign
body inside.
Replace the bad component.
Symptom 10
Abnormal time
Check clock, Backup Cap block, whether it has any component broken, short-
circuit, foreign body, water marks or dusts inside.
Replace the bad component.

Symptom 11
Formula download failure
Check PC link block, whether it has any component broken, short-circuit, foreign
body or dusts inside.
Replace the bad component.
Symptom 12
Abnormal Earphone
Check Headset block, whether it has any component broken, short-circuit, foreign
body or dusts inside.
Replace the bad component.
Symptom 13
LCM backlight abnormal
Check the backlight circuit, whether the surrounding component are normal or not.
Replace the bad component.
Symptom 14
Keypad backlight abnormal
Check backlight LED, whether its surrounding components are normal or not.
Replace the bad component.
Symptom 15
Display antenna squres abnormal
Check whether the antenna splinter is actually the effective connected with PCB
or PAD dusts.
Check the Antenna matching block, whether it has any component broken, short-
circuit, foreign body or dusts inside.
Replace the bad component.