Typically, you will see the background lights on the keyboard illuminate but there will be nothing on the screen. You can try these steps:

  1. Press and hold the ON/OFF button for 30 seconds. The Surface Book should shut down.
  2. Release the ON/OFF button.
  3. Then press and hold the VOLUME+ button (on top of the display next to the ON/OFF button) while also pressing the ON/OFF button for 15 seconds.
  4. A boot screen will appear, click EXIT and Restart.

Please also see these instructions from Microsoft: https://support.microsoft.com/en-us/help/4023537/surface-surface-wont-turn-on-or-wake-from-sleep