Micromax S120 User manual

S120 L3 Service Manual
Micromax S120
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

S120 L3 Service Manual
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 L3 Service Manual
Basic Structure of the Mobile Phone
PCBA Diagrams of S120 Mainboard
Charge MOS tube, charger will
out work if it broken
RF PA,no signal if broken
USB socket,cannot charge and download if
broken
26M crystal,cannot start the phone if broken
Charging connector,cannot start the phone
if broken
CPU,cannot start the phone if broken
TF socket,cannot read T card if
broken
3.5 Heardset if broken

S120 L3 Service Manual
SIM socket,cannot read SIM
card if broken

S120 L3 Service Manual
Camera bonding pad,camera no
function if broken
LCD bonding pad,no display if
broken
Vibrator if broken

S120 L3 Service Manual
3. L3 Level trouble shooting
Please add trouble shooting/ Repairing steps against below given symptoms
Images must paste against every suggested troubleshooting hint
1) Doesn’t Power On
1. Check BAT1 battery socket if welding good
2. Check X101 if normal
3. Check U100 if normal
U100
BAT1
X101

S120 L3 Service Manual

S120 L3 Service Manual
2) Restart / Hang
Same as item 1

S120 L3 Service Manual
3) LCD
1. Check if LCD welding good
2. Check if main board short circuit
J601

S120 L3 Service Manual
4) Touchpad --- NA
5) Proximity Sensor------ NA
6) Accelerometer-------- NA

S120 L3 Service Manual
7) Keypad
1. Check if keypad short circuit
Keypad bonding pad

S120 L3 Service Manual

S120 L3 Service Manual
8) Charging
1. Check if Q350 MOS tube is normal
2. Check if J511 welding good
Q350
J511

S120 L3 Service Manual

S120 L3 Service Manual
9) USB
1. Check if J511 welding good
2. Check if J511bonding pad short circuit
J511

S120 L3 Service Manual

S120 L3 Service Manual
10) Main Camera
1. Check if camera welding good
2. Check if J670 bonding pad short circuit
J670

S120 L3 Service Manual
11) Front Camera------- NA

S120 L3 Service Manual
12) Flash Light
1. Check if Flash Light welding good
2. Check if LED1 bonding pad short circuit
LED1

S120 L3 Service Manual