Operating instructions

No Downstream Signal Lock
72-4017315-01 Rev B 43
No Downstream Signal Lock
After a cable modem powers on and performs an internal self-test, the cable modem
starts to scan for the CMTS downstream channel. The cable modem start its standard
scanning algorithm.
Note: For more information on this process, see Scan for Downstream Channel (on
page 7).
The following table illustrates the status of the front-panel LED status indicators
when the no downstream signal lock condition exists.
LED Label Status
1 POWER ON
2 DS BLINKING
3 US OFF
4 ONLINE OFF
5 LINK ON or BLINKING
6 TEL 1 OFF
7 TEL 2 OFF
8 BATTERY

ON WHEN BATTERY IS CHARGED

BLINKING WHEN BATTERY CHARGE IS LOW

OFF WHEN BATTERY NEEDS TO BE REPLACED (IF
OBSERVED WITH AC POWER APPLIED TO THE MODEM)
Check and Correct
1 On initial installation, or after a reset, allow the cable modem 5 to 8 minutes to
locate and lock on to the downstream channel.
2 Using the Web browser on the PC attached to the cable modem, access the
WebWizard by entering the following IP address: http://192.168.100.1. The Web
browser accesses the WebWizard and the Default page opens.
3 Select the Signal page and verify that the cable modem locks to the downstream
channel of the CMTS.
4 Check the power level and the Signal-to-Noise ratio to verify if it is outside of the
operating range.