What should you check if a USB port that is designed to provide power to a device, even when the PC is shut down, is not providing power when the PC is shut down?
The correct answer and explanation is:
The first thing to check if a USB port designed to provide power to a device when the PC is shut down is not providing power is the BIOS/UEFI settings. Many systems have an option in the BIOS/UEFI that controls whether the USB ports continue to supply power when the PC is off. This feature is usually referred to as “USB Charging in Off Mode” or “ErP” (Energy-related Products). If this setting is disabled, the USB ports will not provide power when the system is off.
Next, check the power settings in the operating system. Some power-saving modes or configurations may restrict the functionality of USB ports, even if they are set to provide power in the BIOS/UEFI. This is less common for dedicated charging ports but should still be ruled out. Also, ensure that the USB port in question is indeed designed to provide power during shutdown. Some ports may only provide power when the system is in sleep mode, not when it is completely powered off.
Additionally, verify that the power supply unit (PSU) is functioning correctly and is capable of supplying power to all components, including the USB ports. If the PSU is not delivering enough power or has a fault, it may fail to supply power to the USB ports when the system is turned off.
Lastly, ensure the USB port and the device connected to it are both working. It’s possible that the USB port itself could be damaged or that the device receiving the power is malfunctioning.
To summarize, the steps to take are:
- Check the BIOS/UEFI settings for USB power options.
- Review the operating system’s power settings.
- Confirm that the USB port is designed to provide power in the off state.
- Ensure the PSU is functioning properly.
- Test the USB port and the device being powered.