This may not be a product fault! Read on:

Almost all Ethernet devices with port status indicators can be used to detect a "carrier signal" on the cable that is plugged into it. The carrier signal is sent by a connected device at a frequency that is dependent on two factors:

1) The link speed set on the port, which is usually automatically negotiated based on the link speed capabilities of the interface

2) The category / quality / length of the Ethernet cable used, as well as the environmental conditions in which the cable run is situated, if auto-negotiation is active

If the link speed of the remote device is not supported, or there is a problem with the cable, The carrier signal may not be detected by one or both interfaces the cable is connected to and the port status indicator will not light on either interface.

The US-16-XG's Ethernet interfaces support 1Gbps and 10Gbps link speeds only. As a result, if the remote device does not support those link speeds, or there is a problem with the cable / cable run conditions, the port will not activate.

To troubleshoot this, try using an alternative cable and/or test against a device you know supports at least 1Gbps link speeds.