A fried Ethernet jack on a device won’t respond to other devices when it’s supposed to be used. Additionally, the computer may report errors with the device or be unable to find it. The possible symptoms of a fried Ethernet jack involve the activity lights staying dark when a cable is plugged in, the connection constantly drops out and the connection not working at all.
The Ethernet adapter might not be the failing network component when showing hardware failure symptoms. Before addressing the Ethernet jack, try swapping the Ethernet cable for one you know is working. If the cable isn’t the issue, try connecting the device another working Ethernet-compatible device like a cable modem, a DSL modem, a router or a hub. For example, the device may be connected to a router and then an outgoing modem, so connecting the device directly to the modem can rule out the router.