This LED will not light up during 10Mbps operation. One function uses a solid green light to indicate that a good link has been established on the network. The other is a flashing green light that indicates when data is being received. Make sure the power is turned on for both the EtheRx Switch and the device it is connected to. The PWR LED should be lit.
Some network adapters require the drivers to be loaded to establish a proper link.
Make sure that the correct cable type is selected. Make sure the cable is wired properly and connected on both ends. If steps 1 through 4 are correct, the cable may be defective or not wired properly. Replace the cable and try again. The TX LED uses a flashing green light to indicate when data is being transmitted.