Linksys WCG200
Power

Off - No Power
Green - Modem has power
Red - Failed Self Test

Internet Cable Flashing - Modem is ranging
On - Modem is online
Internet Activity Flashing - Data going through modem
Ethernet 1,2,3,4 Green - Connection detected
Red - Ethernet Collisions
Flashing - Activity over that port
USB Green - USB Connection Detected
Red - USB Connected but driver not installed/working
Wireless Flashing Green with activity over wireless
Flashes red where there is an issue
Manuals and Support Information
Manual
Manufacturer Site