An Efuse (Electronic fuse) is a one-time programmable (OTP) memory cell inside the SoC. Once a bit is "burned" from 0 to 1, it can never be changed back. Manufacturers use efuses to:
| Device | Chipset | Typical Error Trigger | | :--- | :--- | :--- | | Xiaomi Redmi Note 10 5G | MT6833 (Dimensity 700) | Trying to write preloader without auth | | Realme 8i / Narzo 50 | MT6785 (Helio G96) | Bootloader locked and corrupted system | | Oppo A54 5G | MT6833 | Flashing via SP Flash Tool with generic DA | | Tecno Spark 8 Pro | MT6769 | BROM download without valid authentication file | | Infinix Note 12 | MT6789 | Miracle Box error "BROM DISABLED BY EFUSE" | brom disabled by efuse 0x146 best
| Attempt | Success? | |---------|-----------| | Reinstall drivers | ❌ No | | Use different USB cable/port | ❌ No | | Try older SP Flash Tool | ❌ No | | Use "Authentication Bypass" tools (e.g., MTK Bypass Utility) | ❌ No (most cases) | | Replace the motherboard/CPU | ✅ Yes | | Use EMI (Electronic Manufacturer Interface) auth file | ✅ Yes (rare, expensive) | | Use factory auth server (SLA/DAA unlock) | ✅ Yes (requires leaked server certs/tokens) | An Efuse (Electronic fuse) is a one-time programmable
Summary for the average user: If you see 0x146, your phone is permanently dead for DIY flashing. You cannot bypass it with free tools. Success rate: 95% (if the bootloader is still intact)
The only correct way to bypass the 0x146 restriction is to use an authenticated Download Agent (DA) signed with a key that matches the efuse configuration. Unauthorized DAs (like the generic MTK_AllInOne_DA.bin) will fail immediately.