× Introducing the Orbi 970 Series Mesh System with WiFi 7 technology. For more information visit the NETGEAR Press Room.

Start a New Discussion

Start a New Discussion

Orbi WiFi 7 RBE973
Reply

CM500 Cable Modem Downstream Constantly Flashing Green

deanosauruz
Aspirant
Aspirant
‎2021-09-12 08:16 AM
‎2021-09-12 08:16 AM

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
Model: CM500-1AZNAS|High Speed Cable Modem—DOCSIS 3.0
Message 1 of 7
0 Kudos
Reply
plemans
Guru Guru
Guru
‎2021-09-12 10:11 AM
‎2021-09-12 10:11 AM

Re: CM500 Cable Modem Downstream Constantly Flashing Green

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. 

Message 2 of 7
0 Kudos
Reply
deanosauruz
Aspirant
Aspirant
‎2021-09-14 05:12 PM
‎2021-09-14 05:12 PM

Re: CM500 Cable Modem Downstream Constantly Flashing Green

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

Message 3 of 7
0 Kudos
Reply
deanosauruz
Aspirant
Aspirant
‎2021-09-14 05:40 PM
‎2021-09-14 05:40 PM

Re: CM500 Cable Modem Downstream Constantly Flashing Green

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

Message 4 of 7
0 Kudos
Reply
plemans
Guru Guru
Guru
‎2021-09-14 06:57 PM
‎2021-09-14 06:57 PM

Re: CM500 Cable Modem Downstream Constantly Flashing Green

your cable connections page looks pretty good. 

What router do you have the modem connected to? 

Message 5 of 7
0 Kudos
Reply
deanosauruz
Aspirant
Aspirant
‎2021-09-15 12:49 PM
‎2021-09-15 12:49 PM

Re: CM500 Cable Modem Downstream Constantly Flashing Green

I have an Archer A6 https://www.tp-link.com/us/home-networking/wifi-router/archer-a6/v2.8/ 

Model: CM500|16x4 DOCSIS 3.0 Cable Modem
Message 6 of 7
0 Kudos
Reply
plemans
Guru Guru
Guru
‎2021-09-15 02:17 PM
‎2021-09-15 02:17 PM

Re: CM500 Cable Modem Downstream Constantly Flashing Green

The signal looks good from the quick snapshot that page loads. But your logs indicate the power is going in/out of spec. 

Message 7 of 7
0 Kudos
Reply
Top Contributors
See All
Discussion stats
  • 6 replies
  • ‎2021-09-12 08:16 AM
  • 1017 views
  • 0 kudos
  • 2 in conversation
Announcements

Orbi WiFi 7