Example JTAG usage (high level):
The exact mechanism varies by device and vendor, but the most common scenarios include: brom disabled by efuse 0x146
Employ updated premium tools using specific model exploits tailored for Preloader operations. No USB detection at all. Example JTAG usage (high level): The exact mechanism
If you connect a fully functional, stock phone to SP Flash Tool and attempt to download preloader or DA (Download Agent) without an authorized DA file signed by MediaTek, the BROM reads the eFuse state. Upon seeing that the debug fuse is blown (value = 0x146 status), it refuses the connection and throws the error. Upon seeing that the debug fuse is blown
An (electronic fuse) is a microscopic fuse built into the silicon of the MediaTek processor. Manufacturers can permanently "blow" or burn these fuses during production or via software updates to alter the hardware configuration of the chip irrevocably.