Micromax X556 User manual

S120 L2 Service Manual
Please paste Handset Picture here

S120 L2 Service Manual
1. Technical Specifications :
Please fill below information in Remarks, Below given remarks are for reference only
Particular Remarks
Key Matrix For Flashing SPRD Flashing tool
Chipset SC6531DA
Android Version NA
Processor Frequency 900/1800MHz
Network Mode GSM
ROM 32Mb
RAM 32Mb
Internal memory 4MB
Expandable Memory 8GB
Factory mode code #*868*#
Good Earpiece value in ohms 32 Ohm
Good Loudspeaker value in ohms 8 Ohm
Good Mic value in ohms 330 Ohm
Good Vibrator value in ohms NA
2. CAUTIONS
I. Flashing & Servicing must be undertaken by qualified personnel only.
II. Ensure all work is carried out at an anti-static workstation and that an anti-static wrist strap is worn.
III. Use only approved Tools & components as specified in the parts list.
IV. Ensure all components, modules, screws, and insulators are correctly re-fitted after servicing and
alignment
V. Ensure all cables and wires are repositioned correctly if Handset disassembled
VI. Electrostatic discharge can easily damage the sensitive components of electronic products. Therefore,
Service Centre must adhere the precautions which mentioned above.

S120 L2 Service Manual
3. L2 Level trouble shooting
Please add trouble shooting/ Repairing steps against below given symptoms
Images must paste against every suggested troubleshooting hint
1）Main Components
LED BT
SPK
MIC
Motor

S120 L2 Service Manual
2）Display issue
NO Description Reason Solution
SW FLASH THE SW
Soldering issue Re-soldering the LCD
LCD issue Change the LCD
1
Segments missing, Fading,
Contrast issue, Black lines, Color
issue, Backlight issue, Blank
display, Bad pixel, Flickering
CPU Refer to the service guide L3
2 Mechanically broken LCD issue Change the LCD
Back Camera
LCD
Receiver

S120 L2 Service Manual
3）Camera
NO Description Reason Solution
Soldering issue Re-solder it
Camera issue Change it
1 Bad image
CPU Refer to the service guide L3
Soldering issue Re-solder it
Camera issue Change it
2 Camera not ready
CPU Refer to the service guide L3
Soldering issue Soldering issue
Camera issue Change camera
3 DEAD,No functionality
CPU CPU
4 Canot turn to front
camera Camera issue Change front camera
5 Canot turn to back
camera Camera issue Change back camera
LCD TESTING JIG

S120 L2 Service Manual
4）Speaker
NO Description Reason Solution
The SPK with dust Clean the SPK
SPK foam issue Change it
Spk issue Change it
1 Noise/crack
CPU Refer to the service guide L3
Soldering issue Re-soldering it
SPK issue Change it
2 No volume
CPU Refer to the service guide L3
Soldering issue Re-soldering it
SPK issue Change it
3 Low volume
CPU Refer to the service guide L3
The volume of good SPK is 8Ω +/-0.5
Back camera with
flashlight

S120 L2 Service Manual
5）Microphone
NO
Description Reason Solution
Some dust with MIC Clean the MIC
Assembly issue Assembly it
MIC issue Change it
1 Noise with uplink side
CPUor related component Refer to the service guide L3
Soldering issue Re-solder it
MIC issue Change it
2
Volume low/no
volume with uplink
side
CPUor related component Refer to the service guide L3
3 TDD noise MIC issue Change it
SPK

S120 L2 Service Manual
1, The volume of good mic K is 2.2kΩ +/-0.5%2，Soldering temperature is 330+/-10℃
6）Receiver
NO Description Reason Solution
There is dust with receiver Clean the receiver
Receiver issue Change it
1 Noise/crack
CPU Refer to the service guide L3
Connection issue Assembly it again
Receiver issue Change it
2 No voice/ volume low
CPU Refer to the service guide L3
MIC

S120 L2 Service Manual
1. The volume of RECEIVER is 32Ω +/-15% Ohm(at 1KHZ,179mV input)
7）Vibrator
NO
Description Reason Solution
Motor assembly issue Assembly it again
1 Vibrating is not
properly Motor issue Change it
Motor soldering issue Soldering it again
Motor issue Change it
2 No vibrating
CPU Refer to the service guide L3
 The volume of good Vibrator is 30Ω +/-5%
 Soldering temperature is 330+/-10℃
RECEIVER

S120 L2 Service Manual
8）Battery
NO Description Reason Solution
the voltage of battery is less
than 3.3V
The voltage of battery is more than
1V, and its volume is 150mΩ+/
-10%,
then the battery is good, you can
charge it by DC power (
4V) directly
the voltage of battery is less
than 3.5V
Keep charging it until its voltage to be
3.7V
1 no output
the voltage of battery is 0 Change battery
the voltage of battery is less
than 3.5V
Keep charging it until its voltage to be
3.7V
the voltage of battery is 0 Change battery
2 no charging
CPU or charging IC with issue Refer to the service guide L3
3 Auto charging CPU or charging IC with issue Refer to the service guide L3
Motor

S120 L2 Service Manual
9）Earphone
NO Description Reason Solution
earphone issue change the earphone
Cable broken open the housing of MIC, check and
solder the cable
1 ONE SIDE IS NOT
WORKING
CPU or charging IC with issue Refer to the service guide L3
Cable broken open the housing of MIC, check and
solder the cable
2 Noise
Spk issue Change the earphone
MIC issue Change the earphone
3 MIC is not working
Cable broken open the housing of MIC, check and
solder the cable
3 Can’t end the call by
earphone Assembly issue Open the MIC housing ,check and assembly iy again

S120 L2 Service Manual
 The volume between pin1 and pin4 is 32Ω+/-1Ω, the volume between pin2 and pin4 is 32Ω+/-1Ω, then the spk of earphone is OK;
 The volume between pin3 and pin4 is 2.2KΩ+/-1Ω,then the MIC is OK.
10）Data Cable
NO Description Reason Solution
CABLE ISSUE Change it
CHARGER ISSUE Change it
The I/O connector of PCBA is
with issue Change the I/O connector
1 NO CHARGING
CPU Refer to the service guide L3
2 Canot use DATA D+ or D- is broken Change the data cable
EARPHONE

S120 L2 Service Manual
11）Charger
NO Description Reason Solution
Data cable issue Change the data cable
I/O connector Change the I/O connector
Charger issue Change the charger
1 No charging
CPU Refer to the service guide L3
Data cable issue Change the data cable
I/O connector Change the I/O connector
2 Charging slow
CPU
<VCHG is poor soldering>
Refer to the service guide L3
DATA CABLE

S120 L2 Service Manual
12）No signal
NO Description Reason Solution
the connection of antenna is not
good Assembly it again
SIM issue use a fresh SIM to verify it
SIM slot issue Refer to the service guide L3
RF IC issue Refer to the service guide L3
Calibration data missing Flash the SW
1 No signal
CPU Refer to the service guide L3
CHARGER
CHARGER

S120 L2 Service Manual
13) Bluetooth
NO Description Reason Solution
BT antenna bracket assembly issue Re-assemble
1 No signal
MB is broken Refer to L3 service manual
DATA CABLE
BT

S120 L2 Service Manual
14) Keypad
NO Description Reason Solution
MB is broken
Refer to L3 service manual
1 Keys doesn't work
Keys is broken change it again
15) Flash Light
NO Description Reason Solution
MB is broken
Refer to L3 service manual
1 Light doesn't work
LED is broken change it again
16) FM / Radio
NO Description Reason Solution
No signal
Change a new earphone
1 No signal
Earphone Jack of mainboard issue Refer to L3 service manual

S120 L2 Service Manual
17) Heating
NO Description Reason Solution
Battery issue
Change a new battery
1 Device Heating
MB issue Refer to L3 service manual
18) Memory Card
NO Description Reason Solution
SD Card Issue
Change a new SD card
SD card slot issue Clean SD card Connector
1 SD Card Issue
Still not working Refer to L3 service manual

S120 L2 Service Manual
19) Canot send the SMS/MMS
NO Description Reason Solution
SERVICE NO ISSUE Contact the operator
SIM no service use a fresh SIM to verify it
1
Canot send the
SMS/MMS
Use the 3rd party APK Flash the SW
Thanks
For any query or suggestion please write to [e-mail]