CM700 blinking upstream light

Question

This has happened before and took hours before it magically started working again. Called Comcast, my ISP, and of course they claim everything looks good on their end. Netgear support is a rip off and won’t deal with them. I have checked the cables going to and from the modem and router the best I can and do not see any issues or loose connections. I attached the downstream channels from Netgear genie and will try to attach more photos soon.

Hallywood · Answer

Here are the downstream channels. I do not know how to interpret what any of these channels mean.

Hallywood · Answer

Here are the upstream channels.

FURRYe38 · Answer

Power is kind of all over the place and some are a bit running on the high end of power for the downstream:
https://kb.netgear.com/24311/Power-level-guidelines-for-a-NETGEAR-cable-modem-router
&nbsp;
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
Be sure your using a good quality LAN cable between the modem and router. CAT6 is recommended.&nbsp;What is the brand and model of the host wifi router connected to the modem?
&nbsp;
Have the ISP check the signal and line quality UP to the modem.&nbsp;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.&nbsp;Be sure your using good quality RG6 coax cable up to the modem.&nbsp;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#M12853https://www.duckware.com/tech/solving-intermittent-cable-modem-issues.html

Hallywood · Answer

And finally here is the event log. Comcast claims there is no issue on their end and that a technician needs to look at the modem. I don’t believe that to be true.

Hallywood · Answer

I have checked all connections inside the house. No loose connections, kinks, or anything of the sort. The modem is a Netgear CM700 and the router is a Netgear AC1200 model R6220.

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CM700 blinking upstream light

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