Motorola SB6121 Quick Reference Guide - Page 4

Quick Reference Guide: Motorola SB6121 Start-Up Sequence The SB6121 goes through a series of steps when first connected to power and RF signal. The SB6121 start-up steps are: A. Power On Self Test (POST). If LED remains off, modem is faulty. B. Scanning downstream frequencies. C. Scanning upstream frequencies. D. Downstream and upstream acquired. Modem processing for DHCP, TFTP, and TOD. E. Ready. PC/Activity is solid when a CPE is connected and blinks when transmitting or receiving data. F. Powered off. G. Modem is successfully registered but Network Access Control (NACO) is disabled via DOCSIS® configuration file. H. Performing firmware upgrade DOCSIS 3.0 modems have dual-colored LEDs to visually determine if channel bonding and Gigabit Ethernet is enabled. Troubleshooting Tips Rule out RF Use the front panel LEDs as well as a SLM to rule out potential signal issues. If the RF levels are acceptable, most issues can be corrected by restarting the cable modem. To restart the Motorola SB6121: 1. Shutdown the computer 2. Unplug the cable modem from power and wait approximately 1 minute. 3. Plug the cable modem back into power. 4. Observer the LED light up sequence as detailed above. 5. Restart the computer. LEDs and Error conditions Light RECIEVE SEND ONLINE POWER Turns off during Startup: The downstream (RECEIVE) channel cannot be acquired. The upstream (SEND) channel cannot be acquired. IP registration was unsuccessful. Verify the power connection. Turns off during normal operation: The downstream channel was lost. The upstream channel was lost. IP registration was lost. Verify the power connection. Technical Operations Academy Page 4 of 5