0x146 Best Updated | Brom Disabled By Efuse

It sounds like you’re encountering a low-level boot failure on an embedded system (likely a Rockchip or similar ARM-based SoC), where the mask ROM (BROM) is being disabled due to an eFuse configuration. The code 0x146 typically points to a security or fuse-related policy that prevents further booting.

Here’s a guide to understanding and troubleshooting this issue.

b. Check hardware-level recovery options

• Short test points (D+/D- or recovery pin): Some Rockchip devices can force USB boot by shorting specific pins (e.g., eMMC clock or data pin to ground) during power-on.
• Boot from alternative media (if not fused out): Try SD card with a known working bootloader (e.g., U-Boot or Rockchip MiniLoader).

The Future: Preparing for Efuse 0x146 and Beyond

MediaTek is moving toward full trusted execution environment (TEE) lockdown. Future chipsets may have multiple critical efuses (0x001, 0x146, 0x1A2) that cannot be bypassed by any consumer tool.

For repair shops: Investing in a legitimate service dongle (Octoplus, Chimera, Medusa) is no longer optional—it's mandatory. These dongles receive regular updates with authenticated DAs. brom disabled by efuse 0x146 best

For developers: Never rely on BROM access for custom firmware development. Always unlock the bootloader via fastboot before the device bricks.

1. What the Error Means

• BROM disabled by eFuse: The Boot ROM has been told, via one-time programmable eFuses, to not execute the normal boot flow (e.g., from SD card, USB, or NAND/eMMC).
• 0x146: A status or address code specific to the SoC vendor. In many Rockchip SoCs (RK3328, RK3399, RK356x, RK3588), this can indicate:
  • Secure boot is permanently enabled, and the bootloader signature check failed.
  • eFuse has disabled certain boot sources (e.g., USB download mode).
  • The chip is in a “locked” or “closed” state, meant for production devices.

Solution 2: Hardware Shorting (Test Point + Kamikaze Mode)

This is the technician’s last resort. The principle is to force the CPU into a lower-level BROM mode before the eFuse check is executed.

How it works:

1. Locate the KCOL0 and KROW0 test points (or the specific "BROM download" point) on the PCB.
2. Short the test point to ground (or specific other point) while connecting USB.
3. This triggers a "Kamikaze" or "Force BROM" mode that bypasses eFuse checks temporarily.

Best Tools for this: Easy JTAG, Medusa Pro, or Octopus Box with a proper pinout diagram.

Warning: This requires advanced micro-soldering skills. Incorrect shorting can permanently damage the CPU.

Case Examples: Which Devices Trigger Error 0x146?

| 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" | It sounds like you’re encountering a low-level boot

Why Is This Error Appearing Now?

You may be wondering: "I flashed hundreds of MTK phones before. Why is this happening?"

The answer is MediaTek’s new SLA and DAA security (Secure Layer Authentication and Download Agent Authentication). Starting with Android 10 and widespread on Android 12/13 devices, OEMs began burning these efuses at the factory.

The "BROM disabled by efuse 0x146" error typically appears when: Short test points (D+/D- or recovery pin) :

1. You are trying to flash a device with a locked bootloader.
2. The phone’s preloader is corrupted, forcing BROM mode, but the efuse blocks non-authorized access.
3. You are using an outdated or generic DA file that does not match the exact CPU and security version.