This guide will help you resolve the following issues:
The Nintendo Switch console will not power on.
While in handheld mode or tabletop mode the LCD screen is blank.
After placing the console in sleep mode, it will not wake up when the POWER or HOME Buttons are pressed.
2. Verify Power
Undock your Switch.
With the Switch LCD facing you, align the - symbol on the left Joy-Con with the top left corner of console, and align the + symbol on the Joy-Con with the top right corner of the console.
Using the rail on the side of the console, slide the Joy-Con from top to bottom, until you hear a click.
Reset the AC adapter by leaving it unplugged from both ends for at least 30 seconds.
While unplugged check for any damage to the cable or plug.
Connect the AC adapter to the console and directly to a wall outlet.
3. Manual Update
Select System Settings.
Select System.
Select System Update.
Allow the update to proceed. The system will reboot when ready.
4. Button Restart
Hold the PowerButton for roughly 3 seconds.
5. Dock Check
The next step uses your Switch Dock to determine if the issue is with your AC Adapter or your Switch screen.
6. Switch Dock
Open the back of the Switch dock.
Connect the USB plug from the Nintendo Switch AC adapter into the top terminal of the dock labeled AC ADAPTER, then connect the other end of the AC adapter to a wall outlet.
Connect one end of the HDMI cable into the bottom terminal of the dock labeled HDMI OUT, then connect the other end into an HDMI port on your television or monitor.
Close the back of the Dock.
Position the console so that the LCD screen faces in the same direction as the front panel on the dock, then insert the console into the dock.
Turn the TV set on, and select the correct HDMI input.
7. What's next?
8. Test Another AC Adapter
If possible, test another AC adapter.
If your Switch still does not work after using a new adapter you'll need to have your Switch repaired.
9. What's next?
10. Time to Charge
If the battery is depleted at the time your Switch is plugged in, you will see a power indicator momentarily pop up when the AC adapter is connected to your device. If you see this and the Switch will not power on, allow the device to charge for at least 30 minutes and try to power the unit on again using the power button.