Micromax Q346 User manual

Q346 L2 Service Manual
1. Technical Specifications :
Particular
Remarks
Key Matrix For Flashing
NA
Chipset
SC7731
Android Version
Android5.1
Frequency
GSM：900/1800MHzUMTS：900/2100MHz
Network Mode
Dual SIM: WCDMA+GSM
ROM
8Gb
RAM
1Gb
Internal SD Card memory
NA
Expandable Memory
MB can support up 32 Gb T card
Factory mode code
*#1923#
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.
3. L2 Level trouble shooting
1. Doesn’t power on
NO
Description
Reason
Solution
1
Doesn’t power on
Battery connector dirty
Cleaning the battery connector
Power key FPC badly solder
Re-solder power key FPC

Q346 L2 Service Manual
Power key FPC is broken
Change power key FPC
Power key FPC install badly
Re-install power key FPC
Main PCBA is broken
Refer to L3 service manual
2. RESTART/Hang
NO
Description
Reason
Solution
1
RESTAR/Hang
Software corrupt
Upgrade the SW
power key get stuck,
Assemble the key or attach
power key FPC again
Re-assemble the key or Re-attach power key FPC
Power key FPC badly install
Re-install power key FPC
Main PCBA is broken
Refer to L3 service manual
3. LCD issue
NO
Description
Reason
Solution
1
LCD issue
LCD FPC was installed badly
Re-install LCD FPC
LCD is broken
Replace LCD
Main PCBA is broken
Refer to L3 service manual
Battery
connector
Power key
Power
key FPC
Power key
FPC
Power key
FPC

Q346 L2 Service Manual
4. TOUCHPAD ISSUE
NO
Description
Reason
Solution
1
TP issue
TPFPC was installed badly
Re-install FPC
TP is broken
Replace TP
Main PCBA is broken
Refer to L3 service manual
5. PROXIMITY SENSOR
NA
6. ACCELEROMETER
NO
Description
Reason
Solution
1
ACCELEROMETER
Main PCBA is broken
Refer to L3 service manual
7. Keypad
NO
Description
Reason
Solution
1
Keypad
side key get Stuck, Assemble the
key again
Re-assemble the key again
Power key FPC badly install
Re-install power key FPC
Keypad or Power key FPC is broken
Replace keypad or Power key FPC
TPFPC was installed badly
Re-install TP FPC
TP is broken
Replace TP
Main PCBA is broken
Refer to L3 service manual
LCD
FPC
TP
FPC

Q346 L2 Service Manual
8. Charging
NO
Description
Reason
Solution
1
charging
Charger or battery or USB
cable is broken
Replace charger or battery or USB cable
USB connector is dirty
Clean USB connector
Main PCBA is broken
Refer to L3 service manual
9. USB
NO
Description
Reason
Solution
1
USB
USB cable is broken
Replace USB cable
USB connector is dirty
Clean USB connector
Main PCBA is broken
Refer to L3 service manual
10. Front camera issue
Keypad
Data cable
LCD
FPC
USB connector
USB connector
Keypad

Q346 L2 Service Manual
NO
Description
Reason
Solution
1
camera
Camera FPC is badly install
Re-install camera FPC
Camera is broken
Change it
Main PCBA is broken
Refer to L3 service manual
10. Rear camera issue
NO
Description
Reason
Solution
1
camera
Camera is installed badly
Re-install camera
Camera is broken
Change it
Main PCBA is broken
Refer to L3 service manual
12. Flash light
NO
Description
Reason
Solution
1
Flash light
Camera module is installed
badly
Re-install camera module
Camera module is broken
Change it
Main PCBA is broken
Refer to L3 service manual

Q346 L2 Service Manual
13. Vibrator
NO
Description
Reason
Solution
1
vibrator
vibrator is bad solder
Re-solder vibrator
vibrator is broken
Change it
Main PCBA is broken
Refer to L3 service manual
14. SIM related ISSUE/ Network
NO
Description
Reason
Solution
1
Can’t read SIM
SIM slot pin or SIM pin is dirty
Clean SIM slot pins& SIM PIN
SIM is broken
Change it
Main PCBA is broken
Refer to L3 service manual
2
network
Antenna pin or touch point is
dirty
Clean antenna pin and touch point
Antenna is broken
Change it

Q346 L2 Service Manual
Calibration data missing
Flash the SW
Main PCBA is broken
Refer to L3 service manual
15. 3G-LTE not working
NO
Description
Reason
Solution
1
3G-LTE
Antenna pin or touch point is
dirty
Clean antenna pin and touch point
Antenna is broken
Change it
Calibration data missing
Flash the SW
Main PCBA is broken
Refer to L3 service manual
Clean SIM
PIN
SIM slot
Antenna
Touch point
Clean SIM
PIN
SIM slot
The pin of
Antenna

Q346 L2 Service Manual
16. WIFI/BLUE TOOTH
NO
Description
Reason
Solution
1
WIFI/BT no
signal
Antenna pin or touch point is dirty
Clean antenna pin and touch point
Antenna is broken
Change it
Calibration data missing
Update SW
Change it
Main PCBA is broken
Refer to L3 service manual
17. FM issue
NO
Description
Reason
Solution
1
No signal
SOFTWARE issue
Update SW
Headset is broken
Change it
Earphone jack is broken
Change it
Main PCBA is broken
Refer to L3 service manual
WIFI/BT antenna
The pin of
Antenna
Antenna
Touch point

Q346 L2 Service Manual
18. Heating
NO
Description
Reason
Solution
1
Device heating
battery issue
Change it
Main PCBA is broken
Refer to L3 service manual
19. Earphone
NO
Description
Reason
Solution
1
No function
earphone issue
Change it
Earphone jack is dirty
Clean earphone jack
Earphone jack is broken
Change it
Main PCBA is broken
Refer to L3 service manual
20. Outgoing audio/MIC
NO
Description
Reason
Solution
1
No voice/volume
low
Mic issue
Change it
Mic didn’t place properly
Re-place it
Mic solder issue
Re-solder it
Main PCBA is broken
Refer to L3 service manual
Earphone jack
Earphone

Q346 L2 Service Manual
21. Incoming audio/earpiece
NO
Description
Reason
Solution
1
No voice/volume
low
Receiver pin or touch point is
dirty
Clean receiver pin and touch point
Receiver is broken
change it
Main PCBA is broken
Refer to L3 service manual
22.speaker
NO
Description
Reason
Solution
1
No voice/volume
Speaker’s pin can’t touch the
speaker FPC issue
Re-install speaker or re-attach the speaker
FPC it
The speaker FPC can’t touch the pin
of PCBA
Re-attach the speaker FPC
speaker is broken
change it
Main PCBA is broken
Refer to L3 service manual
MIC
Receiver
MIC