NETGEAR is aware of a growing number of phone and online scams. To learn how to stay safe click here.
Forum Discussion
CBR750 - Downstream light blinking
hey all, Just got an Orbi CBR750 the other day and had comcast come in and replace all the lines. I'm seeing my downstream light continuously blink. Any troubleshooting advice would be greatly ap...
Please post a copy and paste of the modems event log page.
https://kb.netgear.com/30008/How-do-I-view-or-clear-the-event-logs-on-my-NETGEAR-cable-modem-or-modem-router
Have the ISP check the signal and line quality UP to the modem. Be sure the ISP provisions the modem correctly.
Be sure there are no coax cable line splitters in the between the modem and ISP service box.
Be sure your using good quality RG6 coax cable up to the modem.
Start with removing any amplifiers, signal attenuators, or splitters from the coax.
From there check the line for kinks, damage, moisture in the line.
Check the connectors for improperly made ends, foil touching the copper coax line, loose connections, bad/old/cheap connectors, or corroded connections. Replace them if you do.
Be sure to power OFF the modem for 1 minute then back ON.
https://community.netgear.com/t5/Cable-Modems-Routers/General-info-and-Troubleshooting-for-Cable-Modems/m-p/1530376#M12853
https://kb.netgear.com/24311/Power-level-guidelines-for-a-NETGEAR-cable-modem-router
https://www.duckware.com/tech/solving-intermittent-cable-modem-issues.html
Here's a fresh one
| Time | Priority | Description |
| Mar 08 2023 20:18:01 | Critical (3) | Config File Rejected due to Invalid or Unexpected TLV 11 |
| Mar 08 2023 20:18:01 | Critical (3) | Config File Rejected due to Invalid or Unexpected TLV 11 |
| Mar 08 2023 20:18:01 | Critical (3) | Config File Rejected due to Invalid or Unexpected TLV 11 |
| Mar 08 2023 20:18:01 | Critical (3) | Config File Rejected due to Invalid or Unexpected TLV 11 |
| Mar 08 2023 20:18:11 | Warning (5) | RCS Partial Service |
| Mar 08 2023 20:18:19 | Alert (2) | CM Certificate Error |
| Mar 09 2023 07:16:43 | Critical (3) | No Ranging Response received - T3 time-out |
| Mar 09 2023 12:32:18 | Warning (5) | MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1 |
| Mar 09 2023 12:32:18 | Notice (6) | TLV-11 - unrecognized OID |
| Mar 09 2023 12:32:18 | Critical (3) | Config File Rejected due to Invalid or Unexpected TLV 11 |
| Mar 09 2023 12:32:28 | Warning (5) | RCS Partial Service |
| Mar 09 2023 12:32:36 | Alert (2) | CM Certificate Error |
| Mar 09 2023 12:37:40 | Warning (5) | MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1 |
| Mar 09 2023 12:37:40 | Notice (6) | TLV-11 - unrecognized OID |
| Mar 09 2023 12:37:40 | Critical (3) | Config File Rejected due to Invalid or Unexpected TLV 11 |
| Mar 09 2023 12:37:50 | Warning (5) | RCS Partial Service |
| Mar 09 2023 12:37:59 | Alert (2) | CM Certificate Error |
| Time Not Established | Critical (3) | No Ranging Response received - T3 time-out |
| Mar 09 2023 16:44:16 | Warning (5) | MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1 |
| Mar 09 2023 16:44:16 | Notice (6) | TLV-11 - unrecognized OID |
| Mar 09 2023 16:44:16 | Critical (3) | Config File Rejected due to Invalid or Unexpected TLV 11 |
| Mar 09 2023 16:44:26 | Warning (5) | RCS Partial Service |
| Mar 09 2023 16:44:34 | Alert (2) | CM Certificate Error |
| Time Not Established | Critical (3) | No Ranging Response received - T3 time-out |
| Mar 09 2023 17:11:38 | Warning (5) | MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1 |
| Mar 09 2023 17:11:38 | Notice (6) | TLV-11 - unrecognized OID |
| Mar 09 2023 17:11:38 | Critical (3) | Config File Rejected due to Invalid or Unexpected TLV 11 |
| Mar 09 2023 17:11:48 | Warning (5) | RCS Partial Service |
| Mar 09 2023 17:11:56 | Alert (2) | CM Certificate Error |
| Time Not Established | Critical (3) | No Ranging Response received - T3 time-out |
| Mar 09 2023 17:35:12 | Warning (5) | MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1 |
| Mar 09 2023 17:35:13 | Notice (6) | TLV-11 - unrecognized OID |
| Mar 09 2023 17:35:13 | Critical (3) | Config File Rejected due to Invalid or Unexpected TLV 11 |
| Mar 09 2023 17:35:22 | Warning (5) | RCS Partial Service |
| Mar 09 2023 17:35:31 | Notice (6) | CM-STATUS message sent. Event Type Code: 5 |
| Mar 09 2023 17:35:31 | Alert (2) | CM Certificate Error |
| Time Not Established | Critical (3) | No Ranging Response received - T3 time-out |
| Mar 09 2023 17:51:11 | Warning (5) | MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1 |
| Mar 09 2023 17:51:11 | Notice (6) | TLV-11 - unrecognized OID |
| Mar 09 2023 17:51:11 | Critical (3) | Config File Rejected due to Invalid or Unexpected TLV 11 |
| Mar 09 2023 17:51:21 | Warning (5) | RCS Partial Service |
| Mar 09 2023 17:51:29 | Alert (2) | CM Certificate Error |
| Mar 10 2023 10:21:39 | Critical (3) | No Ranging Response received - T3 time-out |
Ya theres line issues here. The ISP needs to review all Alerts, Criticals and Warnings and resolve them.
Thanks for taking a look. Will give comcast a call and see if they can fix it.
Something else to try, someone else posted that they reloaded the CBR750 with the FW update file using a wired PC and web browser, factory reset and setup from scratch help them as well. Something to try in mean time when you can while you wait for the ISP to review the logs.