Own modem not working. Possible signal power issue. Help wanted

[nk2300]

Hello:

To keep it short the Arris 6190 that I was using for 2.5 years stopped working the moment I signed another contract with xfinity. I bough a brand new 6190 but that one also did not worked. Both times the upstream link didn't come up as bonded.  So I bough Netgear CM700.

This Netgear modem shows both upstream and downstrem LED as bonded, it's just the network LED that keeps on blinking. Inretestingly - if the modem is connected and Comcast hasn't activated the modem all LEDs looks good and I'm redirected to some Comcast page to activate the modem. Meaning the Internet works fine with just Comcast website, and DNS works as well.

It's just when modem is activated by Comcast I see network LED blinking non-stop while down/up-stream show bonded. The modem is directly connected to the cable coming from the wall without any splitter or anything else in the way. 3 techs have checked and said signal is good and their own Cisco cable modem works fine.

Either  my modem is blocked or the power level to my suspecion (I guess upstream) is too much. Any help would be greatly appreciated.

(LOGS )When Comcast tried to activate the modem:

Dec 30 2019 07:22:02	Warning (5)	MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1
Dec 30 2019 07:25:00	Critical (3)	SYNC Timing Synchronization failure - Loss of Sync
Dec 30 2019 07:25:06	Warning (5)	Lost MDD Timeout
Dec 30 2019 07:28:40	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out

Signal status:

Frequency start Value
This field below allows you to modify the frequency the cable modem start with its scan during initialization and registration. Enter the new start frequency and restart the cable modem for it to take effect.
Starting Frequency
Startup Procedure
Procedure Status Comment Acquire Downstream Channel 999000000 Hz Locked Connectivity State Ok Operational Boot State Ok Operational Security Enabled BPI+ IP Provisioning Mode Honor MDD honorMdd(4)
Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables UnCorrectables 1 Locked QAM 256 1 519000000 Hz 0.4 dBmV 40.3 dB 0 0 2 Locked QAM 256 2 525000000 Hz 0.2 dBmV 40.3 dB 0 0 3 Locked QAM 256 3 531000000 Hz 0.4 dBmV 40.3 dB 0 0 4 Locked QAM 256 4 537000000 Hz 0.5 dBmV 40.9 dB 0 0 5 Locked QAM 256 5 543000000 Hz 0.2 dBmV 40.3 dB 0 0 6 Locked QAM 256 6 549000000 Hz 0.7 dBmV 40.3 dB 0 0 7 Locked QAM 256 7 555000000 Hz 0.5 dBmV 40.3 dB 0 0 8 Locked QAM 256 8 561000000 Hz 1.0 dBmV 40.3 dB 0 0 9 Locked QAM 256 9 567000000 Hz 1.2 dBmV 40.3 dB 0 0 10 Locked QAM 256 10 573000000 Hz 1.0 dBmV 40.3 dB 0 0 11 Locked QAM 256 11 579000000 Hz 1.7 dBmV 40.9 dB 0 0 12 Locked QAM 256 12 585000000 Hz 1.2 dBmV 40.3 dB 0 0 13 Locked QAM 256 13 591000000 Hz 1.4 dBmV 40.3 dB 0 0 14 Locked QAM 256 14 597000000 Hz 1.5 dBmV 40.9 dB 0 0 15 Locked QAM 256 15 603000000 Hz 1.2 dBmV 40.3 dB 0 0 16 Locked QAM 256 16 609000000 Hz 1.5 dBmV 40.3 dB 0 0 17 Locked QAM 256 17 615000000 Hz 1.0 dBmV 40.3 dB 0 0 18 Locked QAM 256 18 813000000 Hz 2.5 dBmV 40.3 dB 8 0 19 Locked QAM 256 19 819000000 Hz 3.0 dBmV 40.3 dB 0 0 20 Locked QAM 256 20 825000000 Hz 3.0 dBmV 40.3 dB 0 0 21 Locked QAM 256 21 831000000 Hz 3.5 dBmV 40.9 dB 0 0 22 Locked QAM 256 22 837000000 Hz 3.7 dBmV 40.3 dB 0 0 23 Locked QAM 256 23 843000000 Hz 3.2 dBmV 40.3 dB 0 0 24 Locked QAM 256 24 849000000 Hz 3.7 dBmV 41.1 dB 0 0 25 Locked QAM 256 25 855000000 Hz 3.0 dBmV 39.9 dB 0 0 26 Locked QAM 256 26 861000000 Hz 2.7 dBmV 39.9 dB 0 0 27 Locked QAM 256 27 867000000 Hz 2.7 dBmV 39.9 dB 0 0 28 Locked QAM 256 28 873000000 Hz 2.2 dBmV 39.9 dB 0 0 29 Locked QAM 256 29 879000000 Hz 2.0 dBmV 40.4 dB 0 0 30 Locked QAM 256 30 885000000 Hz 1.4 dBmV 39.5 dB 0 0 31 Locked QAM 256 32 891000000 Hz 1.7 dBmV 39.9 dB 4 0 32 Locked QAM 256 31 999000000 Hz 1.2 dBmV 38.9 dB 0 0
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power 1 Locked ATDMA 8 5120 Ksym/sec 17300000 Hz 45.5 dBmV 2 Locked ATDMA 7 5120 Ksym/sec 23700000 Hz 45.3 dBmV 3 Locked ATDMA 6 5120 Ksym/sec 30100000 Hz 45.8 dBmV 4 Locked ATDMA 5 5120 Ksym/sec 36500000 Hz 45.8 dBmV 5 Not Locked N/A Unknown 0 Ksym/sec 0 Hz 0.0 dBmV 6 Not Locked N/A Unknown 0 Ksym/sec 0 Hz 0.0 dBmV 7 Not Locked N/A Unknown 0 Ksym/sec 0 Hz 0.0 dBmV 8 Not Locked N/A Unknown 0 Ksym/sec 0 Hz 0.0 dBmV
Current System Time: Mon Dec 30 20:04:05 2019
System Up Time: 01:56:07

[fragmire]

What you described sounds like what I've been expericing for the past few days.

In short:

• new contract signed, resulting in one of the new speed tiers that's not yet public (200 Mbps, 300 Mbps, 600 or 700 Mbps)
• using a non-Comcast modem

The answer is that the new speed tiers aren't supposed to go live until tomorrow (Jan 7), but some of the configuration changes were already pushed, so the modems have trouble figuring out what to do with it.

The solution is to wait a couple days and try again. The push is supposed to happen tomorrow in stages starting in the morning, so there's no guarantee on when it'll hit your line.

Thread describing my issue and troubleshooting: https://forums.xfinity.com/t5/Your-Home-Network/can-t-connect-to-internet-since-halfway-through-cont...

[fragmire]

From Comcast tech who just visited:

Other modems have resumed operation, but SB6190 still cannot connect, likely due to firmware issues. I'm currently connected via a Motorola MB7621 I bought a few days ago.

The "solution" is to raise the issue with Arris support, so they hopefully acknowledge it and provide a firmware update to Comcast ASAP. Please see https://forums.xfinity.com/t5/Your-Home-Network/can-t-connect-to-internet-since-contract-renewal/m-p... for more detail.

[nk2300]

Hi there:

Really appreciate your reply. I do get some satisfaction that I'm not alone 🙂

Today I'm going to try again using my Netgear 700 modem. Not sure about firmware - because it's the ISP who controlls what firmware the modem should be using as only they control it.  and I guess that is the protocol.

I'm curious if you were suggested by the tech or the Xfinity customer support to get any signal for uplink or downlink changed or anything else?

I'll share my experience later by tonight or tomorrow.

Thanks again!

[fragmire]

Your modem power level and SNR both look fine -- much better than mine, in fact.

My SB6190 is still refusing to connect, and I'm not having any luck with ARRIS customer support. Given that I've had the SB6190 for ~3 years, I've more than recovered its cost through the modem rental fee savings. I'll probably write off the SB6190 as a lost cause and use the Motorola MB7621 instead.

I hope you have better luck than I.

[nk2300]

Hia there:

Based on your feedback I reached out to xfinity customer care and my Netgear CM700 was activated under a minute!

This is totally biazzare how come signing new contract caused a modem to stop working and not just that the even the brand new one didn't work. I returned the Comcast rented modem and want to continue on my Netgear modem.

Thanks again for sharing your feedback. your response was far more helpful than the help from Xfinity!

Good luck with your Motorola modem.

cheers.

Happy  surfing!

[nk2300]

quick note:

My 2.7 year Arris 6190 still showed issues with upstream, while downstarem looked good. Netgear looked good all through. hth!

[fragmire]

Thanks. My MB7621 is happily humming along, and I've returned the Comcast rental.

ARRIS customer service grudgingly agreed to take my report into consideration, but I don't expect much to come out of it, at least not in the short term where it'd matter. I plan to keep the SB6190 around as a backup, since it does have more downstream channels than the MB7621, and may one day become useful again if they fix the issue.

I guess the important part of we're all back online!