Motorola SB5101 modem problems


Hi Optus Tech support

My Motorola SB5101 is developing problems rebooting multiple times during the day.

The error log in the modem shows the problem saying

Priority 3 - Critical   R005.0  Started Unicast Maintenance ranging - No response received - T3 time-out

Priority 4 - Error   C410.1  DCC-ACK not received

Priority 3-Critical  R004.0  Received response to Broadcast maintenance request, but no Unicast maintenance

Priority 6-Notice  M573.0  Modem is shutting down and Rebooting


From searching other websites - it appears there could be problems with either the modem or cable service.

I am in Templestowe.

Anyone else having this problem , and if so how was it resolved .


Many thanks




Re: Motorola SB5101 modem problems

[ Edited ]

Hi @RossH,


Two things I would try:


  1. Contacting Optus Cable Technical Support on 1300 300 693 (call charges may apply), and asking a Technician to conduct a line test (this asesses whether there is a fault from the Modem to the exchange box and, if so, where the fault[s] may lie - this may be likely as you would have had your Cable service for at least 10 years and some wiring may need replacing [I speak from previous experience]);
  2. Asking Optus whether it is possible to receive a complimentary replacement Modem (the Surfboards are the oldest Cable Modems that have been supplied by Optus, from what I recall - furthermore, the latest Cable Modems have other advantages over their Surfboard counterpart).

I'm sure a Moderator would have a few other ideas up their virtual sleeves.


All the best, and keep us posted on how you go!


-Terry (an Optus Customer).

Did this post help? Feel free to give a +Kudos!
Did this post solve your query? Feel free to mark this as the
Accepted Solution!

Post a Reply
Top Contributors
82 Kudos
80 Kudos
68 Kudos
35 Kudos
34 Kudos