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Please take a look at my device info & comment

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Frequent Visitor

Please take a look at my device info & comment

I have a 10 day old subscription and 1 week old modem.  Posting my troubles with the service in another thread did not get any response, so i am wanting to  get comments on  the "signal & logs" that i see in my  device info webpage of comcast.   The cablem modem is new Arris SB6141 from Amazon and it keeps rebooting itself  every hour or two.  Pretty annoying.  I have seen many threads on the same topic, but nothing in those threads helped me understand what the problem is.  Following, i post all that i see in the webpage of comcast regarding the signal & logs.  The only page that seemed useful came up in my internet search, which indicates that Upstream power maybe a suspect. (See DSL Reports discussion)   Is this frequent reboot of modem caused by  comcast  or  Arris SB6141 ?    The logs  can be seen in the  next  post,  since the editor does not allow me to easily cut and copy two images.   Thanks for your help.

 

 

Cable Modem
Status Signal Addresses Configuration Logs Open Source Help
This page provides information about the current upstream and downstream signal status of your Cable Modem.

 

Downstream Bonding Channel Value
Channel ID 15  18  19  20  21  22  23  24 
Frequency 603000000 Hz  621000000 Hz  627000000 Hz  633000000 Hz  639000000 Hz  645000000 Hz  651000000 Hz  657000000 Hz 
Signal to Noise Ratio 38 dB  37 dB  37 dB  37 dB  38 dB  38 dB  38 dB  39 dB 
Downstream Modulation QAM256  QAM256  QAM256  QAM256  QAM256  QAM256  QAM256  QAM256 
Power Level
The Downstream Power Level reading is a snapshot taken at the time this page was requested. Please Reload/Refresh this Page for a new reading
1 dBmV   -1 dBmV   -1 dBmV   0 dBmV   0 dBmV   0 dBmV   1 dBmV   2 dBmV  

 

Upstream Bonding Channel Value
Channel ID 24  21  22  23 
Frequency 36700000 Hz  17300000 Hz  23700000 Hz  30300000 Hz 
Ranging Service ID 9577  9577  9577  9577 
Symbol Rate 5.120 Msym/sec  5.120 Msym/sec  5.120 Msym/sec  5.120 Msym/sec 
Power Level 35 dBmV  34 dBmV  34 dBmV  34 dBmV 
Upstream Modulation [3] QPSK
[3] 64QAM
 
[3] QPSK
[3] 64QAM
 
[3] QPSK
[3] 64QAM
 
[3] QPSK
[3] 64QAM
 
Ranging Status Success  Success  Success  Success 

 

Signal Stats (Codewords) Bonding Channel Value
Channel ID 15  18  19  20  21  22  23  24 
Total Unerrored Codewords 95980057  94968935  94977121  94985306  94960409  94960609  94962478  94962850 
Total Correctable Codewords 13  19 
Total Uncorrectable Codewords 599  536  536  535  646  1505  703 

1399

Accepted Solution

Re: Please take a look at my device info & comment

by

The stats as read at the modem level at that moment in time were o/k but there are three additional signal stats which can't be read by the modem. They can only be read from their end by them polling the CMTS (Cable Modem Termination System) at the local headend facility.

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.

You can call in and ask what these figures are. The Upstream Receive Power Level should fall within the range of -2dB to +2dB with 0dB being in the middle and perfect.

The Upstream SNR should be least 31dB, and the higher it is the better.

The ICFR should be no higher than 2 dB.

You could have an intermittent noise ingress issue in only the upstream channel(s) / return path only somewhere.

They will be able to see whether or not everything is in the green zone and also see a history plot for the modem.

Could also be a firmware glitch or a hardware malfunction. Good luck !

View answer in context
Frequent Visitor

Re: Please take a look at my device info & comment

Here are the logs that  show  how frequently  the reboots are.   In fact,  sometimes  the modem  reboots  within  minutes  of  prior reboot,  and  that  is not  getting  logged  the  second  time around.   I am posting only the first  few,  for the sake of  brevity,  and  since the message  is same  each time a reboot happens  (within 2 hours).

 

Cable Modem
Status Signal Addresses Configuration Logs Open Source Help
This page displays detailed information intended for use by an authorized Motorola Corporation Cable Modem technician.

 

Time Priority Code Message
Apr 18 2017 08:07:50 5-Warning Z00.0 MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=xxxx;CMTS-MAC=xxxx;CM-QOS=1.1;CM-VER=3.0;
Jan 01 1970 00:00:20 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=xxxx;CMTS-MAC=xxxx;CM-QOS=1.1;CM-VER=3.0;
Jan 01 1970 00:00:14 6-Notice N/A Cable Modem Reboot due to power reset ;CM-MAC=xxxx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.0;
Apr 18 2017 03:06:06 5-Warning Z00.0 MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=xxxx;CMTS-MAC=xxxx;CM-QOS=1.1;CM-VER=3.0;
Jan 01 1970 00:00:21 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=xxxx;CMTS-MAC=xxxx;CM-QOS=1.1;CM-VER=3.0;
Jan 01 1970 00:00:15 6-Notice N/A Cable Modem Reboot due to power reset ;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.0;
Apr 18 2017 00:43:30 5-Warning Z00.0 MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.0;
Jan 01 1970 00:00:33 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.0;
Jan 01 1970 00:00:14 6-Notice N/A Cable Modem Reboot due to power reset ;CM-MAC=xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.0;
Apr 17 2017 23:10:10 5-Warning Z00.0 MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.0;
Jan 01 1970 00:00:20 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=xx;CMTS-MAC=xx;CM-QOS=1.1;CM-VER=3.0;
Jan 01 1970 00:00:15 6-Notice N/A Cable Modem Reboot due to power reset ;CM-MAC=xx;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.0;

 


 

 

Status | Signal | Addresses | Configuration | Logs | Open Source | Help

 

 

 

Frequent Visitor

Re: Please take a look at my device info & comment

Something  of  interest (and maybe useful for diagnosis)  is the fact that  the reboots  mostly  happen  when  the  internet connection is being used.  If none of the computers are being  used,  then  the cable modem  does not produce any logs.   This explains  the  sometimes  long  intervals  between the logs.  The logs indicate the times when  modem  is  rebooting,  while  internet is being used at home. 

Connection Expert

Re: Please take a look at my device info & comment

The stats as read at the modem level at that moment in time were o/k but there are three additional signal stats which can't be read by the modem. They can only be read from their end by them polling the CMTS (Cable Modem Termination System) at the local headend facility.

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.

You can call in and ask what these figures are. The Upstream Receive Power Level should fall within the range of -2dB to +2dB with 0dB being in the middle and perfect.

The Upstream SNR should be least 31dB, and the higher it is the better.

The ICFR should be no higher than 2 dB.

You could have an intermittent noise ingress issue in only the upstream channel(s) / return path only somewhere.

They will be able to see whether or not everything is in the green zone and also see a history plot for the modem.

Could also be a firmware glitch or a hardware malfunction. Good luck !




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Frequent Visitor

Re: Please take a look at my device info & comment

Called   technical support line twice to get these numbers.   Once when i called, it was night time and it reached someone in asia and they said they did not  have access to these technical  numbers.  Second time, i spoke to someone in US, and she checkd with the supervisor to find out 2 of these numbers.  Upstream  SNR = 33.1  and   Rx power was 0.0.   But she said that  she did not have ICFR and  that the only way to get that would be to send out a technician  to my home to to measure the signal  levels.    Also, she mentioned that i maybe charged, if  the technician  decided that there was nothing wrong with my  signal levels.  All this within 10 days of  service starting.  I find that it is unreasonable  that comcast would charge  someone,  within 1 month of starting a service,  and i am having  problems.  

 

This is a new modem from Amazon, so luckily i can return and try another one.  Hopefully the problem will go away.

Frequent Visitor

Re: Please take a look at my device info & comment

Changing the modem  (same model number, but new one)  fixed the problem.  Beware of  "refurbished certified"   units from Arris.  This company simply cleans up the modem and resends them with basic testing, in my opinion.  I got 3 consecutive units from Amazon that were all certified refurbished,  but  all of them were still registered to the previous owners;   hence  comcast refused to  activate them and i had to return them all. It took 5  purchases, before  comcast realized my attempts, and thank goodness i got a good customer service rep, who talked to his supervisor to fix my issue.   Reflects very poorly on Arris as a manufacturer, capable of completely making sure that a modem is usable (which in my opinion is "certified refurbished").

Connection Expert

Re: Please take a look at my device info & comment

Glad you got it sorted. Marked "solved" topic now being closed.




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I am not a Comcast employee, I am a paying customer just like you!
I am an XFINITY Forum Expert and I am here to help. For information on the program click here.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark it as an accepted solution!solution Icon
Community Icon
I am not a Comcast employee. I am a paying customer just like you!
I am an XFINITY Forum Expert and I am here to help.
We ask that you post publicly so people with similar questions may benefit.
Was your question answered? Mark it as an accepted solution!solution Icon
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Was your question answered?
Mark it as a solution!solution Icon

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