A

Visitor

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8 Messages

Thu, Jan 13, 2022 12:58 PM

Closed

Started Unicast Maintenance Ranging - No Response received - T3 time-out

My Netgear modem (This is the third replacement unit from Netgear) continues to have the following error. Comcast is no help and basically saying not their modem, not their problem. Can someone please help me fix this or point in the right direction?

Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=[Edited: "Personal Information"];CMTS-MAC=[Edited: "Personal Information"];CM-QOS=1.1;CM-VER=3.0;

EG

Expert

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95.7K Messages

8 m ago

First. Are you actually experiencing any connectivity / performance problems, or are you just focusing on the error log entries ?

Visitor

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8 Messages

8 m ago

Yes, I keep having connectivity issues. 

EG

Expert

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95.7K Messages

@Amare68974

Like what ? Is your connection dropping ? Speed problems ?

What do the modem's signal stats look like ? Try getting them here; http://192.168.100.1 

Please copy all of the text in its entirety of the *Downstream Power Levels*, the *SNR's* (Signal to Noise Ratios), and the *Upstream Power Level* numbers and paste them into your next post.


What is the exact model number of the Netgear device ?

Is this with a WiFi connection ?

 

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Visitor

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8 Messages

8 m ago

Thank you for your time! The wireless connection keeps dropping throughout the day. The modem model is c7000v2. 

Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 25 621000000 Hz 0.6 dBmV 40 dB 0 0
2 Locked QAM256 9 525000000 Hz -0.3 dBmV 39.8 dB 0 0
3 Locked QAM256 10 531000000 Hz 0 dBmV 39.4 dB 0 0
4 Locked QAM256 11 537000000 Hz -0.2 dBmV 39.8 dB 0 0
5 Locked QAM256 12 543000000 Hz -0.4 dBmV 39.9 dB 0 0
6 Locked QAM256 13 549000000 Hz -0.3 dBmV 39.9 dB 0 0
7 Locked QAM256 14 555000000 Hz 0.1 dBmV 40.1 dB 0 0
8 Locked QAM256 15 561000000 Hz 0.1 dBmV 39.2 dB 0 0
9 Locked QAM256 16 567000000 Hz -0.1 dBmV 40.1 dB 0 0
10 Locked QAM256 17 573000000 Hz 0.3 dBmV 40.1 dB 0 0
11 Locked QAM256 18 579000000 Hz 0.3 dBmV 39.9 dB 0 0
12 Locked QAM256 19 585000000 Hz 0.2 dBmV 40 dB 0 0
13 Locked QAM256 20 591000000 Hz 0.1 dBmV 39.6 dB 0 0
14 Locked QAM256 21 597000000 Hz 0 dBmV 39.5 dB 0 0
15 Locked QAM256 22 603000000 Hz 0.1 dBmV 39.8 dB 0 0
16 Locked QAM256 23 609000000 Hz 0.5 dBmV 39.7 dB 0 0
17 Locked QAM256 24 615000000 Hz 0.3 dBmV 40.4 dB 0 0
18 Locked QAM256 26 627000000 Hz 0.4 dBmV 40.3 dB 0 0
19 Locked QAM256 27 639000000 Hz 0.3 dBmV 40.3 dB 0 0
20 Locked QAM256 28 645000000 Hz 0 dBmV 40.3 dB 0 0
21 Locked QAM256 29 651000000 Hz 0.4 dBmV 40.4 dB 0 0
22 Locked QAM256 30 657000000 Hz 0.4 dBmV 40.6 dB 0 0
23 Locked QAM256 31 663000000 Hz 0.4 dBmV 40.4 dB 0 0
24 Locked QAM256 32 669000000 Hz 0.4 dBmV 39.8 dB 0 0
 

 

Visitor

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8 Messages

8 m ago

Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 2 5120 Ksym/sec 29200000 Hz 45 dBmV
2 Locked ATDMA 1 5120 Ksym/sec 35600000 Hz 45 dBmV
3 Locked ATDMA 3 5120 Ksym/sec 22800000 Hz 44.8 dBmV
4 Locked ATDMA 7 5120 Ksym/sec 16400000 Hz 44 dBmV
5 Locked ATDMA 9 1280 Ksym/sec 39600000 Hz 45.5 dBmV
6 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
7 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
EG

Expert

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95.7K Messages

8 m ago

The stats are good.  For a test, does a computer / device that is hardwired directly to the C7000 with an ethernet cable have the same problem ?


With this test, we are trying to isolate this down to being either a WiFi-only problem or a problem with the general connection to the Comcast system which would of course affect both. It's a good step of troubleshooting.

Are there any modem error log entries being shown ? If so, please post them as well in their entirety (copy and paste them, don't post a screenshot) but redact the CM MAC and the CMTS MAC addresses for your privacy. They are considered to be personal information. Personally identifying information is a violation of their forum guidelines. The forum bot will not allow your post to be seen publically.
 

Visitor

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8 Messages

8 m ago

Unfortunately, I currently don’t have any device to directly plug in to the modem. I’ll try to see if can borrow a laptop from someone.


The Activity Log has the following messages (I believe the 1970s entries are after we ended up unplugging the power cord from the modem in hope it would reset and start working again)

1970-1-1, 00:00:44 Notice (6) Honoring MDD; IP provisioning mode = IPv6
1970-1-1, 00:00:40 Notice (6) WiFi Interface [wl1] set to Channel 153 (Side-Band Channel:N/A) - Reason:INIT
1970-1-1, 00:00:40 Notice (6) WiFi Interface [wl0] set to Channel 1 (Side-Band Channel:N/A) - Reason:INIT
1970-1-1, 00:00:37 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=; CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
2022-1-18, 12:23:40 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=  ;CMTS-MAC=; CM-QOS=1.1;CM-VER=3.0;
2022-1-17, 08:22:20 Critical (3) SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=;CMTS-MAC=;CM-QOS=1.1;CM-VER=3.0;
1970-1-1, 00:00:45 Critical (3) No Ranging Response received - T3 time-out;CM-MAC=;CMTS-MAC=;CM-QOS=1.0;CM-VER=3.0;
1970-1-1, 00:00:37 Critical (3) SYNC Timing Synchronization failure - Failed to acquire FEC framing;CM-MAC=; CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.0;CM-VER=3.0;
2022-1-16, 23:57:26 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=;  CMTS-MAC=  ;CM-QOS=1.1;CM-VER=3.0;
2022-1-16, 23:57:25 Critical (3) Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=;CMTS-MAC=  ;CM-QOS=1.1;CM-VER=3.0;

Official Employee

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374 Messages

Hello @Amare68974, thank you for being a part of the Comcast family and for taking the time to reach out to us. Were you able to hook up a laptop/desktop?

I am an Official Xfinity Employee.
Official Employees are from multiple teams within Xfinity: CARE, Product, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Please, mark a reply as the Accepted Answer.tick

Visitor

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8 Messages

Hello there. No, unfortunately I won’t be able to connect a laptop directly for at least another week or so as don’t have one readily available. Since the interruptions happen at random times, I need to have a laptop that can stay connected for a few days.
Every device in the house is connected via wifi at the moment. 

Anna

Official Employee

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312 Messages

@Amare68974

Let's go ahead and take a look at the connection from our end. To get started, could you please send our team a direct message with your full name and full address?

To send a "Peer to peer" message:

• Click "Sign In" if necessary

• Click the "Peer to peer chat" icon

• Click the "New message" (pencil and paper) icon

• Type "Xfinity Support" in the "To:" line and select "Xfinity Support" from the drop-down list which appears. The "Xfinity Support" graphic replaces the "To:" line

• Type your message in the text area near the bottom of the window

• Press Enter to send it

I am an Official Xfinity Employee.
Official Employees are from multiple teams within Xfinity: CARE, Product, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Please, mark a reply as the Accepted Answer.tick

Visitor

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8 Messages

Hi Travis - I’m a little confused. Why would I contact support?

I think there have been three Xfinity technicians by now who came to the house, plugged in their laptops, and basically told me they didn’t see any problems during their visit; and “since it’s not Xfinity’s modem…” 


After the first technician’s visit, I purchased a brand new Netgear modem/router - thinking the old one might have been the culprit. The new one experienced the same issues, however. That’s when the second technician came to my house. He replaced some connections just to be sure but said he found “nothing wrong”. Everything seemed to work for a few days after, and the disconnections started happening again. That’s when the third Xfinity technician came and said maybe I got a lemon from Netgear.
Netgear did a warranty replacement and sent me this current unit; as you can see, I still keep getting the same service interruptions though.

What exactly are you suggesting?

EG

Expert

 • 

95.7K Messages

@Amare68974

Hi Travis - I’m a little confused. Why would I contact support?

To explain this. There are other signal stat figures that can't be read by the modem. They are the "Upstream Rx Power" (Upstream Receive Power Level), the "Upstream SNR Ch." (Upstream Signal To Noise Ratio), and the "Upstream ICFR" (In Channel Frequency Response). These are as equally important in diagnosing connectivity issues as are the modem's stats.

The Comcast corporate employees that are available to these boards will be able to poll the CMTS to see whether or not everything is in the green zone, see your node / cable plant and modem health, and also see a history plot for the modem, and poll for those upstream receive signal stats.

It's your choice if you think that this is of value. Good luck !

I am not a Comcast Employee.
I am a Customer Expert volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Please mark an Accepted Answer!tick

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