Here you can download Spreadtrum SC7731 based PAC Stock Firmware for the Micromax Q331 Android device. The downloadable file High Compressed in an archive, You will get the Flash File after extraction. Included contains Flash Tool, USB Driver, and how-to Flash manual instructions.
[*] Chipset: Spreadtrum SC7731G.
[*] Driver: SPD SCI Android USB Driver.
[*] Flash Tool: SPD Upgrade Tool.
Firmware for Micromax Q331
Build Number: MMX_Q331_SW_V2.0.4_HW_V1.2.0_07312015
Android Version: v4.4.2 (KitKat)
Download Size: 542 MB
Micromax Q331 Flash Tool & USB Driver
Flash Tool for Micromax Q331
Micromax Q331 USB Driver
[*] Backup: During the flashing process SPD Flash Tool will erase user data from the phone. So you need to backup for restoring those files on your device.
[*] Device Information: The Micromax Q331 phone powered by Spreadtrum SC7731 CPU. So you need to use SPD Flash Tools and SPD USB Driver to flash Firmware on this device.
[*] Flashing Information: You can try different types of SPD Flash Tools to flash this Pac file if you see any of them show interrupted in flashing. The following Tools are Upgrade Download, Research Download, and Factory Download.