130 C HAPTER 8: T ROUBLESHOOTING THE NICIf a LNK LED indicates a problem, check the following: Ensure that the network hub or switch and the cableconnecting to the NIC comply with the specificationsappropriate for the network connection. Ensure that the hub or switch is powered on.Viewing the NIC LEDs in the Diagnostics ProgramTo view the LEDs in the 3Com NIC Diagnostics program:1 Make sure that the NIC, the network driver, and the3Com NIC Diagnostics program are installed.2 Open the Windows Start menu.3 Select Programs, and then 3Com NIC Utilities.4 Click 3Com NIC Doctor.The 3Com NIC Diagnostics General screen appears anddisplays following LEDs:Link—lights if there is a valid connection between the NICand the network.Transmit—lights if the NIC is transmitting information.Receive—lights if the NIC is receiving information.Duplex—indicates if the NIC is transmitting data across thenetwork in half-duplex mode (half the LED lights), or infull-duplex mode (the entire LED lights).100LNK(link)On If drivers are installed, the 100BASE-TX connection is active.If drivers are not installed, the NIC is receiving power.Off Something is preventing the connection between the NIC andthe hub or switch.Blinking The cable polarity is reversed. Try a different network cable orcontact the system administrator.ACT(activity)Blinking Network traffic is present.Steady Heavy network traffic is present.Off No network traffic is present.LED State Meaning (continued)For instructions on using the 3Com NIC Diagnosticsprogram, see Running NIC Diagnostics on page 143.
