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

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

 

My modem has these errors.  How do I fix this.

Mon Apr 13 14:36:33 2020   Critical (3)  Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:42:1d:13;CMTS-MAC=00:01:5c:6d:d2:a1;CM-QOS=1.1;CM-VER=3.0; 
Mon Apr 13 14:36:33 2020   Critical (3)  Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:42:1d:13;CMTS-MAC=00:01:5c:6d:d2:a1;CM-QOS=1.1;CM-VER=3.0; 
Mon Apr 13 14:36:33 2020   Critical (3)  16 consecutive T3 timeouts while trying to range on upstream channel 2;CM-MAC=00:40:36:42:1d:13;CMTS-MAC=00:01:5c:6d:d2:a1;CM-QOS=1.1;CM-VER=3.0; 
Mon Apr 13 14:37:02 2020   Critical (3)  Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:42:1d:13;CMTS-MAC=00:01:5c:6d:d2:a1;CM-QOS=1.1;CM-VER=3.0; 
Mon Apr 13 14:37:02 2020   Critical (3)  Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:40:36:42:1d:13;CMTS-MAC=00:01:5c:6d:d2:a1;CM-QOS=1.1;CM-VER=3.0; 
Mon Apr 13 14:37:02 2020   Critical (3)  16 consecutive T3 timeouts while trying to range on upstream channel 1;CM-MAC=00:40:36:42:1d:13;CMTS-MAC=00:01:5c:6d:d2:a1;CM-QOS=1.1;CM-VER=3.0; 
Mon Apr 13 14:37:09 2020   Critical (3)  Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:42:1d:13;CMTS-MAC=00:01:5c:6d:d2:a1;CM-QOS=1.1;CM-VER=3.0; 
Mon Apr 13 14:41:29 2020   Critical (3)  Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=00:40:36:42:1d:13;CMTS-MAC=00:01:5c:6d:d2:a1;CM-QOS=1.1;CM-VER=3.0; 
Mon Apr 13 14:41:41 2020   Notice (6)  Honoring MDD; IP provisioning mode = IPv6 
Mon Apr 13 15:58:13 2020   Critical (3)  Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=00:40:36:42:1d:13;CMTS-MAC=00:01:5c:6d:d2:a1;CM-QOS=1.1;CM-VER=3.0; 

 

 

 

 

   Startup Sequence
 

 

   
   Startup Step Status Comment
 

 



  
   Acquire Downstream Channel 507000000 Hz Locked
 

 


  
   Upstream Connection OK Operational
 

 


  
   Boot State OK Operational
 

 



  
   Configuration File OK  
 

 


  
   Security Enabled BPI+
 

 


  



   Connection Status
 

 

   
   System Up Time 0 days 20h:33m:39s  
 

 


  
   Network Access Allowed  
 

 


  



   Downstream Bonded Channels
 

 

 
 

 


  
   Channel Lock Status Modulation Channel ID Freq. (MHz) Pwr (dBmV) SNR (dB) Corrected Uncorrected
1 Locked QAM256 9 507.0 -2.9 36.5 456 357
2 Locked QAM256 38 417.0 -0.8 40.7 401 245
3 Locked QAM256 39 423.0 -1.3 40.4 419 313
4 Locked QAM256 40 429.0 -1.6 40.3 388 370
5 Locked QAM256 41 435.0 -2.2 40.1 418 343
6 Locked QAM256 1 453.0 -3.2 39.7 381 325
7 Locked QAM256 2 459.0 -3.3 39.7 426 346
8 Locked QAM256 3 465.0 -3.2 39.6 393 271
9 Locked QAM256 4 471.0 -3.1 39.7 459 265
10 Locked QAM256 5 477.0 -3.0 39.7 462 292
11 Locked QAM256 6 483.0 -2.9 39.7 434 330
12 Locked QAM256 7 489.0 -2.7 39.7 451 294
13 Locked QAM256 8 495.0 -2.8 39.6 400 431
14 Locked QAM256 10 513.0 -3.1 39.5 508 224
15 Locked QAM256 11 519.0 -3.3 39.3 395 197
16 Locked QAM256 12 525.0 -3.5 39.2 457 254
Total             6848 4857



   Upstream Bonded Channels
 

 

 
 

 


  
   Channel Lock Status Channel Type Channel ID Symb. Rate (Ksym/sec) Freq. (MHz) Pwr (dBmV)
1 Locked ATDMA 2 5120 29.4 50.8
2 Locked ATDMA 1 5120 35.8 50.8
3 Locked ATDMA 3 5120 23.0 50.5
4 Locked ATDMA 4 5120 16.6 50.8
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Re: Unicast Maintenance Ranging - No Response received - T3 time-out

The upstream power is too high and it may be intermittently fluctuating even higher out of spec. 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.



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Re: Unicast Maintenance Ranging - No Response received - T3 time-out

Upstream there is a device a tech installed a few years ago that's plugged into an outlet with a coax attached to it, could that be a power booster, should I unplug that to troubleshoot?

Nevermind, I just checked on that thing and it doesn't go to anywhere, I think it was take out of the system when the guy came and moved my modem so my son would hard wire his xbox