If holding just the Power button fails, press and hold the Power and Volume Down buttons simultaneously for 15–30 seconds.
Before attempting more advanced resets, try these immediate troubleshooting steps: How to fix ULEFONE Power Armor 13 black screen
This resets the battery management IC. I’ve seen this work on three different Power Armor 13 units. If holding just the Power button fails, press
Because the Power Armor 13 has a non-removable battery, you cannot physically disconnect power. However, you can force a hardware reboot. This clears temporary logic locks that cause the black screen. you cannot physically disconnect power. However
Keep holding until you feel a vibration or see the Ulefone logo appear on the screen. Alternative Combination: If the power button alone fails, try holding Power + Volume Up simultaneously for about 15 seconds. 2. Verify Power and Charging