I am using Fastboot mode to start a Mobile without a power button.
You need two software to start your phone with Fastboot mode without a power button.
1.Minimal ADB Fastboot
2.PDANetA5232
Follow the following Steps to Start your android smartphones without Power Button using Fastboot Mode with PC:
1.Install Minimal ADB on your computer or laptop.
2.Install PDANet for Smartphones in Computer or Laptop.
3.Open Command Prompt form Right-clicking on the windows button.
4.Connect your mobile with pc in Fastboot Mode.
5.Type "cmd" on the search bar and open the command prompt and type "cd/" and press Enter.
6.Type "Fastboot reboot" and press Enter. Your Mobile will be rebooting in few Seconds.
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