Brom Disabled By Efuse 0x146

Title: Understanding BROM Disabled by eFuse 0x146 — Causes, Implications, and Recovery Options

1. Laser Fuse Cutting – Physical modification of the SoC to "unblow" an eFuse. Requires multi-million dollar equipment, decapsulation, and schematic knowledge. Not feasible for repair shops.
2. Fault Injection (Glitching) – Voltage/clock glitching to skip the eFuse read. Demonstrated in labs on older MTK chips, but newer chips include glitch detectors. Extremely low success rate.
3. Boot from eMMC via forced BROM fallback – Some chips check eFuse only for USB BROM. Forcing UART boot might work? Typically, same eFuse disables all external BROM modes.

• Boot the device and capture serial console (UART) output during power-up. Look for SoC identifiers (e.g., “Allwinner sunxi family”, “Amlogic Meson gxbb”, etc.) and the BROM log lines that include “eFuse” messages.
• Example serial capture lines:

  BROM initialised
  BROM disabled by eFuse 0x146
  

• Note chip model strings printed right before or after — essential for mapping fuse semantics.

Test Points:

Shorting test points may still lead to the same 0x146 error if the fuse is global.

• MediaTek BootROM Reverse Engineering (github.com/xyzz/mtk-bootrom)
• eFuse Programming Guidelines (SoC vendor confidential docs, partially leaked)
• “Silicon Demographics: eFuse as a Security Primitive” – IEEE Hardware Security, 2021
• MTKClient source code – BROM handshake failure analysis

7. Conclusion

The causes can vary but typically include: brom disabled by efuse 0x146

0x146

If you are seeing , your device's Boot ROM (BROM) has been permanently disabled via eFuse. This is a hardware-level security measure often used by manufacturers (like Xiaomi or Samsung) to prevent low-level flashing and unauthorized firmware changes. 🧱 What this means Title: Understanding BROM Disabled by eFuse 0x146 —

Marcus handed her a new chip. "That's why we keep pre-efuse samples for development. The error message isn't a bug—it's a feature. It means the security worked exactly as designed. Now you know: never blow efuse 0x146 unless you're ready to say goodbye to the Boot ROM forever." Laser Fuse Cutting – Physical modification of the