The BQ-4028 UP is a compact, entry-level Android smartphone powered by the MT6735 chipset and known for reliable basic use. If your device is stuck on boot, won’t detect SIM, lags, or refuses to turn on, flashing the official ROM can restore system integrity and usability.
Quick Device Specs
- Model: BQ-4028 UP
- Chipset: MediaTek MT6735 (quad-core, 1.3GHz)
- RAM: 512 MB
- Storage: 8 GB (expandable, microSD)
- Display: 4.0″ TFT, 480 x 800 px
- Battery: 1500 mAh removable
- OS: Android 6.0 Marshmallow
Required Downloads
- SP Flash Tool (latest version recommended)
- MTK/MediaTek USB Drivers
- BQ_Mobile_BQ-4028_MT6735_V04_220224_6.0.zip (firmware below)
Official Firmware Download
| Device | Version | Type | Download |
|---|---|---|---|
| BQ-4028 UP | V04_220224_6.0 | Official Scatter ROM | Download V04 (MediaFire) |
How to Flash Firmware on BQ-4028 UP (MTK)
The easiest recovery for BQ-4028 UP is SP Flash Tool. Flashing will erase your device—make a backup if possible. Windows PC and a good quality USB data cable are recommended. See the visual flashing tutorial for each step and troubleshooting in our full MTK guide:
How to Flash Stock Firmware to MediaTek (MTK) Smartphones using SP Flash Tool
Device-Specific Troubleshooting for BQ-4028 UP
- Device won’t turn on, stuck at boot, or no power after flash: Perform a long press (hold Power for 20+ seconds); if unresolved, pull the battery, wait a minute, then retry. If still stuck, repeat the SP Flash Tool flash ensuring you use the correct scatter for MT6735.
- No USB connection or PC fails to detect device: Use updated USB drivers and a different cable/port. Setting phone to “File Transfer” helps, or reset device if needed for persistent errors.
- Lag or unresponsive UI: Clear cached data, uninstall unused apps, and keep only vital apps in use. After flashing, a factory data reset returns smooth stock performance for entry-level hardware.
- IMEI/network not detected: Dial *#06# to check. If blank after flash, restore using SN Writer Tool or similar; always keep IMEI backed up before flashing.
- Display or touchscreen fails: Remove the screen protector, clean the surface, and ensure correct firmware is flashed. Persistent faults may require technical/service center help due to hardware limits.
FAQs
Q1. Does this process wipe user data?
Yes. Flashing resets the phone to factory defaults—save files before you start.
Q2. Can I safely downgrade or upgrade firmware?
Always use the matching version and chipset firmware. Using files for a different model (like MT6570) can brick your phone.
Q3. What do I do if my BQ-4028 UP asks for a privacy password after flash?
Use your original code, or if forgotten, specialist service or Miracle Box tools may be needed.
Q4. How to check or restore IMEI after a flash?
Dial *#06#; if lost, use an IMEI repair tool to restore. See our MTK guide for more.
Q5. My BQ-4028 UP is still laggy after flashing—what else can help?
Disable unused animations, clear background apps, and keep only essential apps installed for best results on 512 MB RAM devices.
See our comprehensive MTK flashing tutorial for extra steps, IMEI info, and hardware-specific advice, or contact BQ support if persistent issues occur.
