I had this issue twice now on the same surface.
The issue is the keyboard and the trackpad will not work, all troubleshooting was done including replacing the keyboard with the Surface Pro 4 keyboard and still no luck.
Just shut down the Surface Pro/2/3 normally using the power button. Then, when it’s off, press the power button and the volume up buttons at the same time, for at least 15 seconds. You may see the screen or the lighting on Type Cover flicker, but keep holding the buttons.
Release the buttons, and let the machine sit for at least 12 seconds. Then, turn it back on normally.
Your system might enter the system bios, just use the keyboard to exit. After booting into Windows your keyboard should work fine again.
Here is how I got my surface pro 3 to finally turn on.
I used Two-button shutdown procedure below:
Don’t use this process on Surface RT or Surface 2.
Use this two-button shutdown process to ensure that Surface is turned off completely.
Step 1: Swipe in from the right edge of the screen, and tap or click Settings, tap or click Power, and then tap or click Shut down to shut down Surface.
If you can’t shut down Surface normally, press and hold the power button on your Surface for 10 seconds.
Step 2: After Surface turns off, press and hold the volume-up button and the power button on your Surface at the same time for at least 15 seconds, and then release both.
The screen may flash the Surface logo, but continue holding the buttons down for at least 15 seconds.
Step 3: After you release the buttons, wait 10 seconds.
Step 4: Press and release the power button on your Surface to turn it back on.
If your Surface still won’t turn on, it needs service. To request service, see Surface Online Service Center.