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T3 timeouts and connection drops

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Regular Visitor

T3 timeouts and connection drops

Upstream Bonding Channel Value @EG

Channel ID
Frequency23700000 Hz 17300000 Hz 30100000 Hz 36500000 Hz 
Ranging Service ID13491 13491 13491 13491 
Symbol Rate5.120 Msym/sec 5.120 Msym/sec 5.120 Msym/sec 5.120 Msym/sec 
Power Level44 dBmV 44 dBmV 45 dBmV 45 dBmV 
Upstream Modulation[2] QPSK
[1] 32QAM
[3] 64QAM
 
[2] QPSK
[1] 32QAM
[3] 64QAM
 
[2] QPSK
[1] 32QAM
[3] 64QAM
 
[2] QPSK
[1] 32QAM
[3] 64QAM
 
Ranging StatusSuccess Success Success Success 
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Regular Visitor

Re: T3 timeouts and connection drops

Channel ID25 26 28 
Frequency591000000 Hz 597000000 Hz 609000000 Hz 
Signal to Noise Ratio26 dB 26 dB 26 dB 
Downstream ModulationQAM256 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
-7 dBmV  

 

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Regular Visitor

Re: T3 timeouts and connection drops

 I am at my wits end. After some storms in my 22206 area code I have had unstable internet for 10 days. The Comcast outage map shows outages all over my area and nothing has helped me regain stability. Modem is sb6181 and at this point The outages are greatly affecting my work from home and might need to switch ISPs. I have tried connection without router as well with same unstable connection. 

Time Priority Code Message

Aug 04 2020 21:21:583-CriticalR02.0No Ranging Response received - T3 time-out;CM-MAC=a4:7a:a4:b7:f3:a1;CMTS-MAC=00:01:5c:b1:ee:72;CM-QOS=1.1;CM-VER=3.0;
Aug 04 2020 21:21:055-WarningZ00.0MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=a4:7a:a4:b7:f3:a1;CMTS-MAC=00:01:5c:b1:ee:72;CM-QOS=1.1;CM-VER=3.0;
Jan 01 1970 00:00:223-CriticalR02.0No Ranging Response received - T3 time-out;CM-MAC=a4:7a:a4:b7:f3:a1;CMTS-MAC=00:01:5c:b1:ee:72;CM-QOS=1.1;CM-VER=3.0;
Jan 01 1970 00:00:166-NoticeN/ACable Modem Reboot due to power reset ;CM-MAC=a4:7a:a4:b7:f3:a1;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.0;
Aug 04 2020 20:56:003-CriticalR04.0Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=a4:7a:a4:b7:f3:a1;CMTS-MAC=00:01:5c:b1:ee:72;CM-QOS=1.1;CM-VER=3.0;
Aug 04 2020 20:55:553-CriticalR02.0No Ranging Response received - T3 time-out;CM-MAC=a4:7a:a4:b7:f3:a1;CMTS-MAC=00:01:5c:b1:ee:72;CM-QOS=1.1;CM-VER=3.0;
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Expert

Re: T3 timeouts and connection drops

The downstream power is on the weak side and the SNR is way too low / out of spec. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, latency problems, and the un-bonding of channels.

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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