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Frequent Modem "Critical" Errors & Reboots

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Frequent Visitor

Frequent Modem "Critical" Errors & Reboots

Here are the signal and log screen captures. Ideas?

 

RachelKlooster_0-1586988673770.png

 

RachelKlooster_1-1586988840928.png

 

 

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Expert

Re: Frequent Modem "Critical" Errors & Reboots

Can't see your pic. Since you are a new poster, it needs to be approved by a Forum Admin. That could take some time. In the interim, you could try hosting it at one of those free third-party pic hosting sites like Imgur or Photobucket and post the link to it here.

 

And please describe your issue with much more details.



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Re: Frequent Modem "Critical" Errors & Reboots

Here links to the images.

 

https://ibb.co/587BBpz

https://ibb.co/Jzn7GVn

 

 

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Expert

Re: Frequent Modem "Critical" Errors & Reboots

The downstream power is low / weak and it may be intermittently fluctuating even lower to out of spec levels. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, and latency problems.

In a self troubleshooting effort to try to obtain better connectivity / more wiggle room, check to see if there are there any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/re-configured. Any splitters that remain should be high quality and cable rated for 5-1002 MHz, bi-directional, and no gold colored garbage types like GE, RadioShack, RCA, Philips, Leviton, Magnavox, and Rocketfish from big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test

If there aren't any unneeded splitters that can be eliminated and if your coax wiring setup can't be reconfigured so that there is a single two way splitter connected directly off of the drop from the street/pole with one port feeding the modem and the other port feeding the rest of the house/equipment with additional splits as needed, and you've checked all the wiring and fittings for integrity and tightness and refresh them by taking them apart then check for and clean off any corrosion / oxidation on the center wire and put them back together again, then perhaps it's best to book a tech visit to investigate and correct.

 

[Edited errors]



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Re: Frequent Modem "Critical" Errors & Reboots

A preliminary review finds no immediate issues with wiring or connections. Could these issues be due to changes beyond the demark just outside of the home? This system has worked well for the past few years and has just started exhibiting these failures last week during a known outage at this address.

 

Is the next test to connect directly to the demark bypassing any internal home wiring? What sort of changes to the readings would be expected?

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Expert

Re: Frequent Modem "Critical" Errors & Reboots


@RachelKlooster wrote:

Could these issues be due to changes beyond the demark just outside of the home? 

 

Yes.

 

Is the next test to connect directly to the demark bypassing any internal home wiring?

 

Yes.

 

What sort of changes to the readings would be expected?

 

Here are the preferred signal ranges;

 

 

Specification      Min             Max
Downstream Power Level    
Cable Modems -10dBmV +10dBmV
Gateways and EMTAs -7dBmV +7dBmV
Downstream Signal to Noise Ratio 35dB -
Upstream Power Level +35dBmV +50dBmV
Upstream Signal to Noise Ratio 31dB -
Upstream Receive Power -2dBmV +2dBmV

 


 



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Re: Frequent Modem "Critical" Errors & Reboots

Modem is now directly connected to the dmark outside the home via one piece of RG59 coax with compression connectors. Here are the new connection readings and a recent event log (Still many T3 timeouts and No Ranging Response events.).

 

However, the connection seems to be more stable, but it hasn't been that long (12 hours or so). 

 

RachelKlooster_0-1587232992043.png

RachelKlooster_1-1587233036286.png

 

 

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Frequent Visitor

Re: Frequent Modem "Critical" Errors & Reboots

External links to the images.

https://ibb.co/8mzyj0d
https://ibb.co/VwK8wDJ

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New Poster

Re: Frequent Modem "Critical" Errors & Reboots

I've had service for 4 days now and have had to reboot it twice. Horrible service
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Expert

Re: Frequent Modem "Critical" Errors & Reboots

The upstream power is still too high. I would book a tech visit for this one. Bear in mind that if the premises facing techs can not find or fix a problem at your home, it is they who are responsible for escalating it to their line / network / maintenance dept. techs. The problem may lie beyond your home in the local neighborhood infrastructure somewhere but it is their S.O.P. to start at the home.
 

Also keep in mind that you may not be able to get a tech visit at this time due to COVID 19. Good luck !



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Re: Frequent Modem "Critical" Errors & Reboots

Thank you for all of the help. What is the recommended strategy for scheduling a successful tech support visit?

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Expert

Re: Frequent Modem "Critical" Errors & Reboots

1800comcast.



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Re: Frequent Modem "Critical" Errors & Reboots

A service call is now scheduled for tomorrow (Tuesday 4/21) AM. The requested task is to confirm operation of the cabling/signaling at the demark box outside the house. The modem is currently working. What should I make sure gets checked while the Tech is onsite? Any other tips for service visits?

 

Here are the current signal readings & log.

RachelKlooster_0-1587385611865.png

RachelKlooster_1-1587385723379.png

 

EXTERNAL LINKS

https://ibb.co/JHdVF1H
https://ibb.co/mbNFd1W

 

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Expert

Re: Frequent Modem "Critical" Errors & Reboots

Show them this thread. Good luck with it ! Please post back with how it goes.



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Re: Frequent Modem "Critical" Errors & Reboots

PROBLEM FIXED!!!

 

The tech showed up ontime and after an initial inspection ended up making two significant changes. An ingress filter was removed immediately outside the house in the plastic demark box AND the cable was replaced from the pole to the house. The ingress filter must have been installed sometime in the past and was no longer needed after testing the current in-house wiring. The cabling to the poll was "crackling" when it was being coiled up for disposal so it was definitely showing its age. Everything has been looking good now for about a week. See current signal and event log captures below.

 

Thanks for the help with this. Overall a true success story of the forum system working.

 

RachelKlooster_0-1588000126175.png

RachelKlooster_2-1588000163296.png

 

EXTERNAL LINKS

https://ibb.co/9r2g1bT

https://ibb.co/R9HxVb2

 

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Expert

Re: Frequent Modem "Critical" Errors & Reboots

Looks good ! Happy surfing !



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