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deanosauruz's avatar
deanosauruz
Aspirant
Sep 12, 2021

CM500 Cable Modem Downstream Constantly Flashing Green

My Modem Details: 

 
Hardware VersionC312T00-01
 
Firmware VersionV1.01.12
 
Cable Modem Serial Number48L50B7FA3805
 
CM CertificateInstalled
 
CM MAC94:a6:7e:18:35:bc

 

 

My Issues
For the last week I have noticed download speeds have been a little troublesome. 
I browsed some discussions here and found people posting their modems logs, so i thought I'd take a look at mine and i see CRITICAL and WARNING everywhere. 

I have no idea what the language means so i felt posting here was the best solution to hopefully rectifying why the downstream light keeps blinking green

Modem Logs

2021-9-12, 14:52:57Warning (5)MDD message timeout;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 14:52:56Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 14:01:25Warning (5)MDD message timeout;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 14:01:06Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 13:54:37Warning (5)MDD message timeout;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 13:54:33Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 12:50:08Warning (5)MDD message timeout;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 12:50:04Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 12:38:11Warning (5)MDD message timeout;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 12:36:44Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 11:38:20Warning (5)MDD message timeout;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 11:38:08Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 11:14:11Warning (5)MDD message timeout;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 11:13:59Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 11:08:36Warning (5)MDD message timeout;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 11:08:24Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 10:42:57Warning (5)MDD message timeout;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 10:42:54Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 10:32:06Warning (5)MDD message timeout;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 10:31:33Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 07:05:30Warning (5)MDD message timeout;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 07:05:29Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 05:39:21Warning (5)MDD message timeout;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 05:39:12Critical (3)Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 00:45:22Warning (5)MDD message timeout;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-9-12, 00:44:32Notice (6)TLV-11 - unrecognized OID;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
1970-1-1, 00:00:30Notice (6)Honoring MDD; IP provisioning mode = IPv4
1970-1-1, 00:00:21Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:21Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:21Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:31Critical (3)No Ranging Response received - T3 time-out;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:21Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:27Critical (3)No Ranging Response received - T3 time-out;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:21Critical (3)SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:21Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:33Critical (3)No Ranging Response received - T3 time-out;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:21Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
2021-5-26, 01:47:22Critical (3)No Ranging Response received - T3 time-out;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.0;CM-VER=3.0;
2021-5-26, 01:47:12Critical (3)Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=94:a6:7e:18:35:bc;CMTS-MAC=00:01:5c:79:c6:4f;CM-QOS=1.1;CM-VER=3.0;
2021-5-26, 01:47:11Critical (3)SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=94:a6:7e:18:35:bc;CMTS

6 Replies

  • plemans's avatar
    plemans
    Guru
    Sep 12, 2021

    Your logs are indicating line issues. 

    do you have a screen snip of the cable connections page? 

    Check for splitters, signal attenuators, and amplifiers in line. Remove them if you do. 

    check the line for kinks, damage, old/loose/bad/corroded connections and replace them if needed. 

    I'd move the modem to right where the coax enters the home and connect it there. 

    • deanosauruz's avatar
      deanosauruz
      Aspirant
      Sep 15, 2021

      After checking the cables I find no erosion ordamaged cables, and I do not have any splitters, signal attenuators, and amplifiers. 
      the modem is as close to the coax entry point as physically possible. 

      Could there be a damaged line outside? 

      I speed test and i get acceptable speeds yet sometimes a website on my desktop will show a DNS failed page buit then within seconds suddenly appears to load the page....

      I have attached a screen capture of the connections page

      • deanosauruz's avatar
        deanosauruz
        Aspirant
        Sep 15, 2021

        For some reason the attached image didn't appear with my reply.