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The upstream LED on the modem starts flashing and our internet service drops

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New Poster

The upstream LED on the modem starts flashing and our internet service drops

There is an ongoing issue with our internet service dropping multiple times a day.

 

The upstream LED on the modem starts flashing and our internet service drops for many minutes.

 

The modem logs the following errors around the time of the service interuptions.

 

2020-5-24, 10:12:40 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out
2020-5-24, 09:24:26 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out
2020-5-24, 02:12:28 Critical (3) No Ranging Response received - T3 time-out
2020-5-24, 02:12:19 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 1
2020-5-24, 00:29:37 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out
2020-5-23, 21:28:12 Critical (3) Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out
2020-5-23, 14:21:40 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 1
2020-5-23, 13:02:56 Critical (3) 16 consecutive T3 timeouts while trying to range on upstream channel 1


The power on the upstream channels tends to creep up until the outage occurs. Normally, the power is in the mid to upper 30's.

 

Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 55 5120 Ksym/sec 30100000 Hz 48 dBmV
2 Locked ATDMA 53 5120 Ksym/sec 17300000 Hz 51.3 dBmV
3 Locked ATDMA 54 5120 Ksym/sec 23700000 Hz 49.5 dBmV
4 Locked ATDMA 56 5120 Ksym/sec 36500000 Hz 45.5 dBmV


Upstream Bonded Channels (Partial Service)
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 55 5120 Ksym/sec 30100000 Hz 42 dBmV
2 Not Locked Unknown 53 0 Ksym/sec 17300000 Hz 0.0 dBmV
3 Locked ATDMA 54 5120 Ksym/sec 23700000 Hz 43.5 dBmV
4 Locked ATDMA 56 5120 Ksym/sec 36500000 Hz 39.5 dBmV


We have tried using the techinician chat four times now.

 

On the third chat, we were told a techinician was scheduled to come out on 5/21 between 5 and 7 PM and were given a CR* reference number. A technician never showed.

 

On our fourth chat the next day, the technician could not find that ticket number in the system and said no techinican was booked to come out. The technician mentioned that he could see the issue had been ecalated. They offered to arrange a technical callback for me and said "Got it, you will get a call in a few hours. And at the same time you can also request for a callback at https://www.xfinity.com/support/schedule-callback to speak to an agent. This was said on Friday. It is now Sunday and I have not recieved a call back yet.

 

With two people working full time at home, internet service interuptions are causing huge issues.

 

How can I get this issue resolved?

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New Poster

Re: The upstream LED on the modem starts flashing and our internet service drops

Downstream Bonded Channels
Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1 Locked QAM256 32 585000000 Hz 3.6 dBmV 39.2 dB 7617 6496
2 Locked QAM256 33 591000000 Hz 3.7 dBmV 39.1 dB 8411 7195
3 Locked QAM256 34 597000000 Hz 3.6 dBmV 39 dB 9406 6837
4 Locked QAM256 35 603000000 Hz 2.9 dBmV 38.8 dB 10397 7028
5 Locked QAM256 36 609000000 Hz 2.7 dBmV 38.8 dB 10323 6952
6 Locked QAM256 37 615000000 Hz 2.5 dBmV 38.6 dB 10889 6719
7 Locked QAM256 38 621000000 Hz 2.4 dBmV 38.6 dB 11227 6947
8 Locked QAM256 39 627000000 Hz 2.5 dBmV 38.5 dB 11474 6807
9 Locked QAM256 40 633000000 Hz 2.4 dBmV 38.4 dB 14097 7245
10 Locked QAM256 41 639000000 Hz 2.5 dBmV 38.1 dB 14959 7377
11 Locked QAM256 42 645000000 Hz 2.3 dBmV 38.3 dB 12758 7192
12 Locked QAM256 43 651000000 Hz 2.1 dBmV 38.3 dB 14081 6906
13 Locked QAM256 44 657000000 Hz 2.1 dBmV 38.3 dB 11826 7235
14 Locked QAM256 45 663000000 Hz 2 dBmV 38.1 dB 13894 7267
15 Locked QAM256 46 669000000 Hz 2.2 dBmV 38.2 dB 14096 7140
16 Locked QAM256 47 675000000 Hz 2.3 dBmV 37.6 dB 14345 4504
 
Upstream Bonded Channels
Channel Lock Status US Channel Type Channel ID Symbol Rate Frequency Power
1 Locked ATDMA 55 5120 Ksym/sec 30100000 Hz 39.5 dBmV
2 Locked ATDMA 53 5120 Ksym/sec 17300000 Hz 38.8 dBmV
3 Locked ATDMA 54 5120 Ksym/sec 23700000 Hz 39.5 dBmV
4 Locked ATDMA 56 5120 Ksym/sec 36500000 Hz 39 dBmV
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Expert

Re: The upstream LED on the modem starts flashing and our internet service drops

In your first post, the upstream power is on the high side and it may be intermittently fluctuating even higher to out of spec levels. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, and latency problems.

 

Something intermittent is going on with your connectivity.

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.



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