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Modem T4 time out error - Received Response to Broadcast Maintenance Request.....

Frequent Visitor

Modem T4 time out error - Received Response to Broadcast Maintenance Request.....

Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;

 

 

For past 2 days I am seeing a lot of these error on my modem logs.

 

It has worked perfectly for almost 6 months now. And suddenly this has started.

 

Modem is  Motorola 6121.

 

Below are the signal stats. I dont have a splitter. Modem is directly connected to the coaxial cable

 

Downstream 

----------------

Channel ID                             3  1  2  6 

Frequency                              663000000 Hz  651000000 Hz  657000000 Hz  681000000 Hz 

Signal to Noise Ratio              37 dB  37 dB  37 dB  38 dB 

Downstream Modulation        QAM256  QAM256  QAM256  QAM256 

Power Level                            0 dBmV   0 dBmV   0 dBmV   -1 dBmV  

 

Upstream

-------------

Channel ID                             9 

Frequency                               22000000 Hz 

Ranging Service ID                10153 

Symbol Rate                           2.560 Msym/sec 

Power Level                            57 dBmV 

Upstream Modulation             [3] QPSK
[2] 16QAM
[3] 64QAM

Ranging Status                        Success 

 

Signal stats(codewords)

------------------------------

Channel ID                             3  1  2  6 

Total Unerrored Codewords   349582866  349582872  349582869  349582881 

Total Correctable Codewords 34  32  29  21 

Total Uncorrectable Codewords 642  643  649  648 

 

 

 

I chatted with comcast customer care yesterday & she went over re-starting modem & router citing that modem was out of sync with the server. And rebooting has got it into sync.

 

It worked after that till today afternoon, where it started the same problem again.

 

My logs are full of these errors.

 

Jun 16 2014 16:44:27 5-Warning Z00.0 MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=90:3e:ab:92:0e:88;CMTS-MAC=00:01:5c:22:32:84;CM-QOS=1.1;CM-VER=3.0;

 

Jan 01 1970 00:00:13 6-Notice N/A Cable Modem Reboot due to T4 timeout ;CM-MAC=90:3e:ab:92:0e:88;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.0;

 

Jun 16 2014 16:43:37 3-Critical R04.0 Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=90:3e:ab:92:0e:88;CMTS-MAC=00:01:5c:22:32:84;CM-QOS=1.1;CM-VER=3.0;

 

Jun 16 2014 14:33:07 5-Warning Z00.0 MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=90:3e:ab:92:0e:88;CMTS-MAC=00:01:5c:22:32:84;CM-QOS=1.1;CM-VER=3.0;

 

Jan 01 1970 00:26:16 3-Critical R04.0 Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=90:3e:ab:92:0e:88;CMTS-MAC=00:01:5c:22:32:84;CM-QOS=1.1;CM-VER=3.0;

 

Jan 01 1970 00:23:32 3-Critical R06.0 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=90:3e:ab:92:0e:88;CMTS-MAC=00:01:5c:22:32:84;CM-QOS=1.1;CM-VER=3.0;

 

Jan 01 1970 00:23:32 3-Critical R03.0 Ranging Request Retries exhausted;CM-MAC=90:3e:ab:92:0e:88;CMTS-MAC=00:01:5c:22:32:84;CM-QOS=1.1;CM-VER=3.0;

 

Jan 01 1970 00:23:30 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=90:3e:ab:92:0e:88;CMTS-MAC=00:01:5c:22:32:84;CM-QOS=1.1;CM-VER=3.0;

 

Jan 01 1970 00:22:28 3-Critical R04.0 Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=90:3e:ab:92:0e:88;CMTS-MAC=00:01:5c:22:32:84;CM-QOS=1.1;CM-VER=3.0;

 

Jan 01 1970 00:21:58 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=90:3e:ab:92:0e:88;CMTS-MAC=00:01:5c:22:32:84;CM-QOS=1.1;CM-VER=3.0;

 

Jan 01 1970 00:21:11 3-Critical R04.0 Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=90:3e:ab:92:0e:88;CMTS-MAC=00:01:5c:22:32:84;CM-QOS=1.1;CM-VER=3.0;

 

Jan 01 1970 00:18:30 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=90:3e:ab:92:0e:88;CMTS-MAC=00:01:5c:22:32:84;CM-QOS=1.1;CM-VER=3.0;

 

Jan 01 1970 00:18:16 3-Critical R04.0 Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=90:3e:ab:92:0e:88;CMTS-MAC=00:01:5c:22:32:84;CM-QOS=1.1;CM-VER=3.0;

 

Jan 01 1970 00:17:00 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=90:3e:ab:92:0e:88;CMTS-MAC=00:01:5c:22:32:84;CM-QOS=1.1;CM-VER=3.0;

 

Jan 01 1970 00:16:46 3-Critical R06.0 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=90:3e:ab:92:0e:88;CMTS-MAC=00:01:5c:22:32:84;CM-QOS=1.1;CM-VER=3.0;

 

Jan 01 1970 00:16:46 3-Critical R03.0 Ranging Request Retries exhausted;CM-MAC=90:3e:ab:92:0e:88;CMTS-MAC=00:01:5c:22:32:84;CM-QOS=1.1;CM-VER=3.0;

 

Jan 01 1970 00:16:44 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=90:3e:ab:92:0e:88;CMTS-MAC=00:01:5c:22:32:84;CM-QOS=1.1;CM-VER=3.0;

 

Jan 01 1970 00:15:50 3-Critical R04.0 Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=90:3e:ab:92:0e:88;CMTS-MAC=00:01:5c:22:32:84;CM-QOS=1.1;CM-VER=3.0;

 

Jan 01 1970 00:15:20 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=90:3e:ab:92:0e:88;CMTS-MAC=00:01:5c:22:32:84;CM-QOS=1.1;CM-VER=3.0;

 

Jan 01 1970 00:14:33 3-Critical R04.0 Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=90:3e:ab:92:0e:88;CMTS-MAC=00:01:5c:22:32:84;CM-QOS=1.1;CM-VER=3.0;

 

 

Not sure whats going on.

 

Can someone plz help ?

Problem Solver

Re: Modem T4 time out error - Received Response to Broadcast Maintenance Request.....

 

 

Upstream  "Power Level 57 dBmV",   if thats not a typo, the upstream power level is way too high.

& there's no upstream channel bonding setting up.  Would expect to see 3 or 4 upstream channels.

(However i don't know how many upstream channels there should be for the  Performance Starter 6meg internet or lower speed service, if you have one of those.) 

If you are connecting directly to the cable that enters the house, (no splitters or line amp somewhere else in house between that wall connection & the outside cable), then other than replacing that inside cable,  you'd want to call to get a Comcast tech out to check the signal levels & see about getting the upstream down to a reasonable level.  (like 50 to 51 dbmv)

 

 

If you own the Moto 6121 modem & it somehow turns out to be your modem, or some wiring in your house, they'll charge you for the visit.   A safe thing to do is get the Service Protection Plan at $3 to $4 per month, then call in to get the Tech visit.   You can always cancel the service plan some later month.

Service Protection Plan - http://www.comcast.com/spp

 

 

Frequent Visitor

Re: Modem T4 time out error - Received Response to Broadcast Maintenance Request.....

Its performance pack 25/5.

 

There are two cable coming out of wall. One of which I have connected to modem.

Other is not being used.

 

On 6/15, when i was on chat with comcast customer care & she asked me to power reboot modem & router, I had checked the signals & upstream power level was 46 dBmV. But after that it again went back to 57 dBmV.

 

It has been the same since last 6 months. But it has not created any issue till now.

Problem Solver

Re: Modem T4 time out error - Received Response to Broadcast Maintenance Request.....


manish1211 wrote:

 

There are two cable coming out of wall. One of which I have connected to modem.
Other is not being used.

 


 

If both cables are active Comcast cables, that suggests a splitter either behind the wall plate or at the other end of those cables at some point where they connect to the main cable coming into the house.

 

The main test you want to do is connect the modem (directly) to the main cable coming into the house with no splitters or amps inbetween.  If signals are way off there also, call to get a tech out,   if signals are good there, start looking at cables & splitters inside the house, (keep in mind as you prev mentioned, the modem can boot up & have good signal at that moment, then change back to being way off).  So  i'd still suggest getting the service protection plan and then calling to get a Tech out.  

 

If you decide to check out the inside wiring,   check connections, remove any unnecessary splitters, replace necessary spliters, etc.   If your not using that second cable you mentioned, remove the splitter that feeds it, if there is one.   Ideally you want one 2 way splitter with one side going to modem & other feeding everything else in house, if you have cable tv also.

 

If you're able to isolate a cause and fix before the tech visit, just cancel the visit.   

 

   

Frequent Visitor

Re: Modem T4 time out error - Received Response to Broadcast Maintenance Request.....

I just verified the two cables.

 

They are coming from outside of the wall to the inside.

 

Outside

There seems to be a cable coming from somewhere (probably pole). That is connected to the splitter, from where 3 cables are emerging.

 

Two of them are coming in my appt thru the wall. One is going somewhere. Probably to the appt. above me.

 

I am not sure if i can connect my modem to the cable coming from modem by removing the splitter (which is on the outer side of the wall). This might interupt someone else's service.

Problem Solver

Re: Modem T4 time out error - Received Response to Broadcast Maintenance Request.....

 

Yep sounds more & more like something for a Tech to look at.

 

Problem Solver

Re: Modem T4 time out error - Received Response to Broadcast Maintenance Request.....


manish1211 wrote:

I just verified the two cables.

 

They are coming from outside of the wall to the inside.

 

Outside

There seems to be a cable coming from somewhere (probably pole). That is connected to the splitter, from where 3 cables are emerging.

 

Two of them are coming in my appt thru the wall. One is going somewhere. Probably to the appt. above me.

 

I am not sure if i can connect my modem to the cable coming from modem by removing the splitter (which is on the outer side of the wall). This might interupt someone else's service.


If you are the person paying the bill then you are the only one that should be on that cable run. If it is a tap from pole to your apt rather than a line to a junction box inside apt complex it is a single user connection.

Was this a pre-exsisting cableing run when you moved in?

Frequent Visitor

Re: Modem T4 time out error - Received Response to Broadcast Maintenance Request.....

Yes. This was an existing setup when I moved in. I had my own modem. So I just connected it, called comcast & they provisioned it over the phone itself. No tech person visited my place.

Problem Solver

Re: Modem T4 time out error - Received Response to Broadcast Maintenance Request.....

Okay that 3rd line bugs me, no idea where it goes and what it does. You are paying for the service and that line isn't yours.

You might remove the 3 way splitter, replace with a good quality 2 way, or if you invest in the $6 a month wiring protection plan for a couple months have CC tech clean up your internal wiring. No idea why you have 2 cables in from outside unless going to different locations inside apt. would think 1 line and a single 2 way splitter going cable one side and modem other a lot cleaner.

Signal is way out of whack, clearing up the local possibilities may solve or at least clear up the root cause for solving.

Frequent Visitor

Re: Modem T4 time out error - Received Response to Broadcast Maintenance Request.....

For past 3 weeks I was not facing this issue. However the problem has started from a couple of days again.

 

I investigated about the 3 way splitter outside my wall. Only one cable is coming in my appt, which is connected to modem. Two cables are emerging from the splitter going to someone else's appt.

 

Below is the current upstream signal levels. still at 57 dBmV

 

Upstream Bonding Channel Value

Channel ID
Frequency22000000 Hz 
Ranging Service ID15722 
Symbol Rate2.560 Msym/sec 
Power Level57 dBmV 
Upstream Modulation[3] QPSK
[2] 16QAM
[3] 64QAM
 
Ranging StatusSuccess 

 

Problem Solver

Re: Modem T4 time out error - Received Response to Broadcast Maintenance Request.....

 

Should get a tech out to "fix"  your signal levels.

 

Here's a thought though since you have access to the outside box.

Try putting a regular 2 way splitter between the drop line from the street and the existing 3way splitter. 

One side of 2way splitter to cable going to your apt, and other side going to input of the 3way splitter for the other other apts.  See if that gives you better signals.