The error is a hardware-level security restriction found on newer MediaTek (MTK) devices, particularly those from brands like Vivo . It indicates that the manufacturer has permanently "blown" an eFuse—a one-time programmable bit—to block access to the Boot ROM (BROM) mode. What This Error Means
Because the direct BROM entry is locked, you must use alternative methods to "force" the device into a flashable state: Test Point (Hardware Shorting)
: This involves opening the device and physically bridging two specific points on the motherboard (Test Points) while connecting the USB cable. This can sometimes force the device into a "Preloader" mode that allows flashing even if BROM is disabled Authorized Flash Tools brom disabled by efuse 0x146 best
| Prevention | Action | |------------|--------| | from an unknown source. Uncheck PRELOADER in SP Flash Tool. | ✅ | | Do not downgrade from Android 11 to 10 or 9 on MediaTek. | ✅ | | Block OTA updates if you plan to flash custom ROMs. | ✅ | | Backup full firmware (including preloader) before updating. | ✅ | | Use MTK Client or SP Flash Tool readback before making changes. | ✅ |
: If the security is not the absolute latest, you can try the Python-based MTK Bypass Utility The error is a hardware-level security restriction found
This article provides the technical breakdown and practical solutions for the "BROM disabled by efuse 0x146" error. We will explore what BROM and eFuse are, why 0x146 specifically appears, and the most effective strategies to bypass or resolve it.
If you see 0x146 , your phone is permanently dead for DIY flashing. You cannot bypass it with free tools. This can sometimes force the device into a
| 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" |