Caution: This requires opening the device and carries a high risk of permanent damage. Using Preloader Mode Newer tools like UnlockTool ChimeraTool MTK Client GUI attempt to communicate via the instead of the BROM. Ensure you have the specific DA (Download Agent)
If you are reading this, you have likely been staring at a flashing tool log (SP Flash Tool, Miracle Box, or CM2 MT2) that suddenly halted progress with the dreaded error:
Instead of forcing the device into BROM, you target the Preloader using specialized device definitions (EMI files) that act as an authorized handshake.
: When eFuse 0x146 is active, holding Vol + and Vol - often triggers a fast charging state instead of a boot sequence. Try connecting the device with Volume Down only , or no keys at all . brom disabled by efuse 0x146 best
Plug the USB cable into the phone. Watch the log window in the utility. If successful, the software will state Jumping to BROM... OK and display your chipset parameters, completely ignoring the 0x146 hardware error flag. Important Precautions
Because this is a hardware-level lock, "best" depends on how far you are willing to go. 1. The Preloader Method (Software) Instead of BROM, most modern tools now use the .
Safely remove the back cover of the phone and disconnect the battery. Caution: This requires opening the device and carries
The error message is a critical security message encountered on MediaTek (MTK) chipset-powered devices. It signifies that the device's Boot Read-Only Memory (BROM), which handles early-stage booting and firmware flashing, has been permanently disabled via a physical security measure known as an eFuse .
If you’ve ever tried to unbrick or flash a modern MediaTek (MTK) device and were met with the error you know the frustration. This isn't just a simple software bug; it's a hardware-level security implementation designed to block unauthorized access to the BootROM.
This "tricks" the CPU into thinking there is a hardware error, sometimes forcing it into a state where it will accept commands despite the efuse. 3. Authorized Auth (Official) : When eFuse 0x146 is active, holding Vol
: Instead of targeting BROM, tools send authorization keys directly to the device's Preloader partition (the secondary stage bootloader).
For modern devices with heavily restricted eFuses, manufacturers require an authorized server token to authorize BROM access.