Hello Dawn724, Thank you for contacting the Microsoft Support Community.
I'm sorry to hear that your Surface Pro 4 is not turning on properly. Here are some steps you can try to fix the issue (sorry if this is duplicate to what you've already tried).
- Make sure your Surface is plugged in and press and hold the power button for 30 seconds, then release it. This will force a shutdown and restart your device.
- If the screen is still black, press and hold the power and volume down buttons for 15 seconds, then release them. This will perform a two-button shutdown and reset your device. I know you tried this but give it another shot.
- You can also try to wake the screen, use one of the following keyboard shortcuts: Windows logo key+ Por Ctrl + Alt + Del. Or for a black screen, use the following keyboard shortcut: Windows logo key + Ctrl+ Shift+ B.
If none of these steps work, please let us know and we'll see if there are other steps we can try.
Thanks for the question!