Hi, ishikaagrawal!
Thanks for reaching Microsoft Community. We are sorry to learn you have issues with your Surface Pro 7 shutting down randomly. Thanks for taking the time to let us know about this. We need to gather information regarding this.
- What is your Windows version and OS Build? Press Windows and type winver to obtain this.
- When did the issue start?
- Any changes made on the device?
- Are there accessories connected to your device (Type Cover, SD card, Surface Dock, charger, etc.)?
- Troubleshooting steps aside from the Surface Diagnostic Toolkit you mentioned.
- Does this happen on any activity on the device? Please enumerate them.
- Does it happen with and without Internet connection?
- Does it happen when running on battery power? How about when plugged into its charger?
- Have you tried to force shutdown the device and restart?
- Press and hold the power button until the screen turns off (about 10 seconds), then release the power button.
- Press and release the power button to turn your Surface back on. You should see the Microsoft logo.
If that doesn't work, here's how to make sure your Surface turns off completely:
Press and hold down the power button until your Surface restarts and you see the Windows logo screen (about 20 seconds), then release the power button.
For the meantime, please follow the steps below.
1: Check for Windows Update
2: Update drivers and firmware
Check what is the current OS Build of your Windows version by going to Settings > System > About.
Go to Download driver and firmware for Surface, choose Surface Pro 7 then click Download on the next page.
Choose the .msi file that matches your current OS Build and click Next.
After downloading, run and install the .msi then Restart.
3: Run System File Checker
Please check this link for the steps in Using the System File Checker Tool in Windows 10
We hope this helps you out, we highly encourage you to inform our Community by clicking on Yes or marking my post as an answer. This will help other members who may have the same issue as you. Otherwise, don't hesitate to update us so we can further assist you.
Kind regards,
Janette_Z