Symptoms

The Thunderbolt USB Type-C ports on the computer may continue to output power to charge other devices when the computer is powered off. Affected Platforms: Dell 14 Premium DA14250Dell 16 Premium DA16250Precision 3550Precision 5550Precision 5750XPS 13 9300XPS 14 9440XPS 15 9500XPS 16 9640XPS 17 9700

Cause

If the computer is connected to the AC power supply, the Thunderbolt USB Type-C Power Delivery function is energized. Any peripheral device such as cell phone, Bluetooth device connected to the computer to charge continues to charge while the computer itself is powered off.

Resolution

The computer is functioning per the design specification. There is no option to disable the Thunderbolt USB Type-C Power Delivery in the computer BIOS. To deenergize the ports, you must also disconnect the AC Adapter from the computer.

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