The SM3 Slim Mechanical Keyboard (ST-BTSMKW3) may not turn on if the battery is depleted, the power switch is off, or there is a hardware issue.

To troubleshoot:

1. Connect the keyboard to a power source using the included USB-C cable and charge it for at least 30 minutes.
2. While charging, check for a charging indicator LED.
3. Make sure the power switch is in the ON position.
4. After connecting the USB-C cable, press any key. Even if the battery is fully depleted, the keyboard may still operate in wired mode.

If the keyboard does not show a charging indicator and remains unresponsive while connected via USB-C, please contact Customer Support for warranty assistance.