CM600 Please check RF connection

[Pkdan1]

Hi,

I have a CM600 that suddenly stopped working. When i log into the modem it says “your modem is offline please check the RF connection”. I called xfinity and they said everything is good on their end but can’t connect to the modem. In settings, one channel is locked. Does anyone have any ideas on how to troubleshoot this? Attached is the event log.

[Pkdan1 · Accepted solution]

It turns out my neighbors dog bite my line… xfinity was able to run a new line and everything is fix now. Thanks for the help!

[Pkdan1]

Hmm I can’t post a .jpeg so I’ll type it.
Time not established critical 3 - No UCDs received -timeout
Time not established critical 3 - sync timing synchronization failure- failed to acquire Qam/qpsk
Time not established critical 3 sync failure failed to acquire fec framing

[Pkdan1]

Channel 1 locked, modulation QAM256, Chanel Id 12, frequency 495000000hz, power -25.5dBmv, SNR 26.8 dB, correctable 36203440, incorrectables 1838213. Everything else is not locked.

[FURRYe38]

Please post a copy and paste of the modems connection status and event log page.
https://kb.netgear.com/30007/How-do-I-obtain-the-cable-connection-information-from-a-NETGEAR-cable-m...
https://kb.netgear.com/30008/How-do-I-view-or-clear-the-event-logs-on-my-NETGEAR-cable-modem-or-mode...

You correct and un-correctables should be zero. 

https://www.duckware.com/tech/solving-intermittent-cable-modem-issues.html

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 to check all fittings as well. 
Be sure your using good quality RG6 coax cable up to the modem. 
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-Mod...

Check power levels:

https://kb.netgear.com/24311/Power-level-guidelines-for-a-NETGEAR-cable-modem-router?article=24311

[Pkdan1]

My downstream power is -20.5dBmV. Does that mean it’s an issue with the cable?

[plemans]

Yes, if you're at -20dbmv, you have a line issue. 

Move the modem right where the coax comes into the home and direct connect it. 

See if that works. If it doesn't, then its something exterior to the home causing the issue and the isp needs to come check the line. 

If it connects, post a screensnip of that cable connections page. It'll let us see how the incoming signal is and if its something interior to the home you need to work on or if the signal is still poor. 

[Pkdan1 · Accepted solution]

It turns out my neighbors dog bite my line… xfinity was able to run a new line and everything is fix now. Thanks for the help!

[plemans]

Glad you got it resolved!