cromax X245 User manual

X245 L2 Service Manual
SERVICE MANUAL

X245 L2 Service Manual
CAUTIONS
Please refer to the phone’s user’s guide for instructions relating to operation, care, and maintenance, which include
important safety information.
Servicing and alignment must be undertaken by qualified personnel only.
Ensure all work is carried out at an anti-static workstation and that an anti-static wrist strap is worn.
Use only approved components as specified in the parts list.
Ensure all components, modules, screws, and insulators are correctly re-fitted after servicing and alignment
Ensure all cables and wires are repositioned correctly
Electrostatic discharge can easily damage the sensitive components of electronic products. Therefore, every service
supplier must observe the precautions which mentioned above.
CONTENTS
Content
1. Brief Introduction….……………………………………………………………………………….….3
2. Tools……………………………………………………………………………………………………..5
3. Picture of main board
A&B side of PCBA .…………….…………………………………………………….…………..18
A&B of PCBA Layout………….….………….…………………………….………………….…....19
4. System Block Chart…………………………………………………………………………………...20
5. Unit Circuit Map ..….........................................................................................................21

X245 L2 Service Manual
CHAPTER1INTRODUCTION
SPEC：
Network：2 band，850/1900, 900/1800
Size：120*49.8*12.65mm
Lithium Battery:1000MAH
USB:Micro USB 2.0
Main Function
Bar functionphone
MT 6260M
2.4 QVGA 320*240
0.3 Mega-H /1.3 Mega-S
Dual SIM

X245 L2 Service Manual
CHAPTER 2、SERVICE TOOLS
Voltage regulator
Multimeter
Iron
Hot air gun
Solder wire, soldering paste
Computer and software download cable
Metal tweezers, Screw driveretc
Pick
Driver
Tweezers
Wrist
groun
ding
strap
Antistatic
gloves
SW
upDownlo
ad cable

X245 L2 Service Manual
CHAPTER4.SYSTEM BLOCK DIAGRAM
5.1、PCBA A-Side
PCBAB-Side
J701 LCD connector No
display or display
abnormality
J702 camera
connector
Bug by no
camera .
Keypad bug by
no function
J401 Earphone
connector
Bug by damaged.
Earphone no audio.
U101 CPU Bug by
damaged Can’t power
on. No RF signal. No
display or display
abnormality
J404 T-Flash connector
Bug by damaged
Can’t Access T card.
J405 I/O connector.Bug
by damaged.
No charge.
U302 RF PA
Bug by damaged.
No signal. Large
current
J201 Battery connector
Bug by damaged.
Not power on.

X245 L2 Service Manual
Side A layout
Side B layout

X245 L2 Service Manual
CHAPTER6 TROUBLESHOOTING
CANNOT POWER ON-CURRENT SWING INSTABILITY
Upgrade the
software is normal?
Cannot power on
Replace the
structuralmember.
Check the battery is
normal?
Check the battery
connectorin normal?
Replacethe PCBA is
normal?.
Replace the battery.
NO
NO
yes
NO
Replace the battery
connector.
yes
yes
Replace the PCBA.
NO

X245 L2 Service Manual
REPAIR FLOW FOR PHONE DEAD
Phone dead
Upgrade the software can
settle the defect issue?
Clean and reinstall
the keypad or replace
the touch panel.
Check battery connector
and battery touch point if
is dropped or dirty?
Check the keypad if stuck
or touch panel do not work
to make the phone “dead”?
Replace the PCBA
Clean or replace
the battery or
battery connector.
YES
YES
No
No
No

X245 L2 Service Manual
NO DISPLAY OR DISPLAY ABNORMALITY
No display or display
abnormality after power on
Check LCD connector
is OK or not
Change LCD connector
can settle the defect
issue?
Replace the PCBA.
Check LCD if damage or
liquid flow out
Change LCD
Yes
Clean or reweld
the LCD connector
Yes
Change the LCD can
settle the defect
issue?
No
Upgrade software
No

X245 L2 Service Manual
INSERT SIM REPAIR PROCESS
NO
Replace SIM card
Replace the
PCBA.
Insert SIM
Clean or replace
SIM connector.
Clean or reweld the
SIM connector
Check SIM connector
is OK or not
OK
Check if all the SIM
pins are clean
NO
Check FPC on SIM
connector is OK or not
NO
Replace FPC
NO
Upgrade softwarecan
settle the defect issue?
NO

X245 L2 Service Manual
N0/WEAK SIGNAL TROUBLE SHOOING
No or weak
signal
Inspect the antenna and
antenna connector to see
if there’s any distortion
Replace the
defective
components.
Check and replace RF
connector to see if there’s
any signal
Replace RF
coaxial line
Replace the PCBA.
YES
YES
Check and replace RF
coaxial line to see if there’s
any signal .
YES
Replace RF
connector
NO
NO

X245 L2 Service Manual
NO/LOW SOUND FROM SPEAKER
Set the phone as
normal mode
Replace the PCBA
No sound or noise
Remove the speaker and
measure with multimeter
to see if there’s any
sound.
Replace speaker.
The phone is
inSilent mode.
Check and replace
FPC is ok or not.
.
Replace FPC.
Yes
NO
yes

X245 L2 Service Manual
RECEIVER LOW VOICE OR NO VOICE
Measure the signal
with oscillograph
under calling mode
Receiver is low.
Check if receiver
connector is damaged.
Resolder or clean the
receiver connector.
Check if the receiver is
broken or damaged
Yes
NO
NO
Replacethe
receiver.
Replace the PCBA.

X245 L2 Service Manual
NO/LOW SOUND FROM MIC
No/Low sound from
MIC
NO
Yes
YES
Check if there’s
MIC cover
Install the MIC
cover.
Press power on and side
buttonto test mode and
activate echo loop,
Replace the MIC
Replace FPC to check if
the problem is solved
Replace the
FPC
Replace the PCBA
YES

X245 L2 Service Manual
Upgrade the software
Check charger and cable without
problem, or change good one
Upgrade the
software is normal?
No charge
DOES NOT CHARGE –NO CHARGE IN
YES
NO
NO
NO
NO
Change battery
Check if I/O connector
works normal
Check and replace
FPC is normal
YES
Replace the PCBA.
Replace the charger
or cable without
Re-solder or replace
the I/O connector
Replace the FPC

X245 L2 Service Manual
CAN’T READ T-FLASH CARD
Can’t read
T-Flash card
NO
NO
Check if T-Flash slot
appearance was ok?
Replaced the
T-Flash slot
Check if T-Flash
FPC is normal?
Re-solder or
replace
FPC.
NO
Check if the T-Flash
connector is normal?
Re-solder or replace
the T-Flash connector.
Replace the
PCBA.
NO

X245 L2 Service Manual
WIFI、BT、FM 、GPS DEFECT REPAIR FLOW CHART
YES
NO
WIFI or BT or FM or
GPScan’t open，
Can’t work normal
Software update and check
the function is OK or not
Upgrade Software
Check the WIFI or GPS antenna
is normal?
Check WIFI or GPS RF
connector is normal?
Replace the RF
connector
Replace the PCBA.
NO
Replace the
antenna.