In today’s guide we are going to learn how to reboot to Emergency Download Mode (EDL). It allows you to unbrick your device, unlock bootloader and even modify device parameters. To reboot into EDL Mode is easy if ADB interface is accessible. This line of code “adb reboot edl” will work perfectly.
But the problem is that many bricked PDA can’t be booted in EDL Mode if FastBoot Mode is not accessible, even if you have full ADB support. If Bootloader is locked there is no chance to flash a partition or boot an image.
There are some firmware that support rebooting to EDL in Android Bootloader using the command “reboot-edl” but FastBoot doesn’t recognize “reboot-edl” in the command line so it doesn’t send the command to the device.
FastBoot protocol is very easy and simple. It is text-based and it’s enough to send a packet containing “reboot-edl” command text over USB. The easiest way to do this is to patch Windows fastboot.exe file. Replacing “reboot-bootloader” with “reboot-edl” will get the work done.
“Reboot-bootloader” string is found in the command line, fastboot.exe. So if we change the “reboot-bootloader” with “reboot-edl”, you will specify the “reboot-edl” in the command line and this text will be sent to the device.