Panasonic Toughbook CF-C1ADAAZ6M Reference Manual page 175

Hardware Diagnostics
When the Icon Becomes Gray and the Corresponding Device
Cannot Be Checked
The device is disabled in the Setup Utility:
Set the device to [Enabled] in the Setup Utility.
The USB icon is gray:
The USB 2.0 port is disabled, or the USB 3.0 port is damaged.
Set [USB Port] to [Enabled] in the [Main] menu of the Setup Utility.
If the icon remains gray, the USB 3.0 port may be damaged.
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