Help! I am at the mercy of my Modem Nighthawk C7000-100NAS

Question

Constant disconnection issues everyday. Cannot get any work done. I've rebooted numerous time, bought new coax cable, change my service to static ISP, change the MTU to lower numer than 1500, called Xfinity, etc. You name it, I've tried it.

Here is my event log from this morning just to show some examples. Any help would be appreciated. I shelled out $200 for this modem so stable connection should be the least of my worries :(

Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 12:03:06	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 12:02:51	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 12:02:46	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 12:01:59	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 12:01:46	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 12:01:31	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 12:01:26	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 12:00:39	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 12:00:26	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 12:00:11	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 12:00:06	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:59:19	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:59:06	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:58:51	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:58:46	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:57:59	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:57:46	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:57:41	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:57:26	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:57:09	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:56:23	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:56:05	Notice (6)	Honoring MDD; IP provisioning mode = IPv6
2020-9-8, 11:54:50	Critical (3)	No Ranging Response received - T3 time-out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.0;CM-VER=3.0;
2020-9-8, 11:54:31	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:54:24	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:53:51	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:53:04	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:52:51	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:52:37	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:52:31	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:51:45	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:51:32	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:51:17	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:51:12	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:50:25	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:50:12	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:49:57	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:49:52	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;
2020-9-8, 11:49:05	Critical (3)	Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out;CM-MAC=08:36:c9:59:33:f8;CMTS-MAC=00:38:df:9a:8d:cc;CM-QOS=1.1;CM-VER=3.0;

plemans · Answer

t3/t4 errors tend to be signal issues. do you have a screen snip of tthe cable connections page? it shows the values

SunGodxApollo · Answer

Frequency start ValueThis field below allows you to modify the frequency the cable modem start with its scan during initialization and registration. Enter the new start frequency and restart the cable modem for it to take effect.Starting Frequency&nbsp;Startup ProcedureProcedureStatusCommentAcquire Downstream Channel483000000 HzLockedConnectivity StateOKOperationalBoot StateOKOperationalSecurityEnabledBPI+IP Provisioning ModeHonor MDDhonorMdd(4)&nbsp;Downstream Bonded ChannelsChannelLock StatusModulationChannel IDFrequencyPowerSNRCorrectablesUncorrectables1LockedQAM2565483000000 Hz-1.4 dBmV42.6 dB002LockedQAM25613543000000 Hz-1.8 dBmV41.9 dB003LockedQAM25614549000000 Hz-1.3 dBmV42.2 dB004LockedQAM25615555000000 Hz-1.1 dBmV42.3 dB005LockedQAM25616561000000 Hz-1.9 dBmV41.8 dB006LockedQAM25618573000000 Hz-2.4 dBmV41.6 dB007LockedQAM25619579000000 Hz-2.9 dBmV41 dB008LockedQAM25620585000000 Hz-2.6 dBmV41 dB009LockedQAM25621591000000 Hz-2.9 dBmV40.6 dB0010LockedQAM25622597000000 Hz-2.3 dBmV41 dB0011LockedQAM25623603000000 Hz-2 dBmV41.3 dB0012LockedQAM25624609000000 Hz-2.2 dBmV41.2 dB0013LockedQAM2561459000000 Hz-1.2 dBmV42.6 dB0014LockedQAM2562465000000 Hz-1.4 dBmV42.5 dB0015LockedQAM2563471000000 Hz-1.3 dBmV42.7 dB0016LockedQAM2564477000000 Hz-1 dBmV42.9 dB0017LockedQAM2566489000000 Hz-1.3 dBmV42.5 dB0018LockedQAM2567495000000 Hz-1.6 dBmV42.5 dB0019LockedQAM2568507000000 Hz-0.8 dBmV43.1 dB0020LockedQAM2569513000000 Hz-1.4 dBmV42.6 dB0021LockedQAM25610519000000 Hz-1.5 dBmV42.5 dB0022LockedQAM25611525000000 Hz-2.3 dBmV41.9 dB0023LockedQAM25612531000000 Hz-2.7 dBmV41.9 dB0024LockedQAM25617567000000 Hz-1.9 dBmV42.5 dB00&nbsp;Upstream Bonded Channels (Partial Service)ChannelLock StatusUS Channel TypeChannel IDSymbol RateFrequencyPower1LockedATDMA15120 Ksym/sec30100000 Hz51.5 dBmV2LockedATDMA25120 Ksym/sec36500000 Hz49 dBmV3Not LockedUnknown30 Ksym/sec17300000 Hz0.0 dBmV4Not LockedUnknown40 Ksym/sec23700000 Hz0.0 dBmV5Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV6Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV7Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV8Not LockedUnknown00 Ksym/sec0 Hz0.0 dBmV

plemans · Answer

you only have 2 locked upstreams channels. coupled with your t3t4 errors, did comcast every come out and check the line?&nbsp;

SunGodxApollo · Answer

How can I make them Locked? I've spoken to them on the phone and they tested their service and said it was running fine. I've been disconnected at least 15 times this morning. More than usual. Usually is 2-3 times a day.&nbsp;

plemans · Answer

Its a line/modem issue.&nbsp;Either the modem's going bad (doubtful) or the line has issues. Their first response is always "our lines fine" because then they have to send a tech out to check it and it costs them $.&nbsp;if you can, make sure there's no splitters, attenuators, amplifiers in line. Also, move the C7000 to right where the coax enters the home. This prevents the issues from being the wiring within the home. Most isp's charge if the fix/problem is interior to the home.&nbsp;

Forum Discussion

Help! I am at the mercy of my Modem Nighthawk C7000-100NAS

5 Replies

Procedure	Status	Comment
Acquire Downstream Channel	483000000 Hz	Locked
Connectivity State	OK	Operational
Boot State	OK	Operational
Security	Enabled	BPI+
IP Provisioning Mode	Honor MDD	honorMdd(4)

Channel	Lock Status	Modulation	Channel ID	Frequency	Power	SNR	Correctables	Uncorrectables
1	Locked	QAM256	5	483000000 Hz	-1.4 dBmV	42.6 dB	0	0
2	Locked	QAM256	13	543000000 Hz	-1.8 dBmV	41.9 dB	0	0
3	Locked	QAM256	14	549000000 Hz	-1.3 dBmV	42.2 dB	0	0
4	Locked	QAM256	15	555000000 Hz	-1.1 dBmV	42.3 dB	0	0
5	Locked	QAM256	16	561000000 Hz	-1.9 dBmV	41.8 dB	0	0
6	Locked	QAM256	18	573000000 Hz	-2.4 dBmV	41.6 dB	0	0
7	Locked	QAM256	19	579000000 Hz	-2.9 dBmV	41 dB	0	0
8	Locked	QAM256	20	585000000 Hz	-2.6 dBmV	41 dB	0	0
9	Locked	QAM256	21	591000000 Hz	-2.9 dBmV	40.6 dB	0	0
10	Locked	QAM256	22	597000000 Hz	-2.3 dBmV	41 dB	0	0
11	Locked	QAM256	23	603000000 Hz	-2 dBmV	41.3 dB	0	0
12	Locked	QAM256	24	609000000 Hz	-2.2 dBmV	41.2 dB	0	0
13	Locked	QAM256	1	459000000 Hz	-1.2 dBmV	42.6 dB	0	0
14	Locked	QAM256	2	465000000 Hz	-1.4 dBmV	42.5 dB	0	0
15	Locked	QAM256	3	471000000 Hz	-1.3 dBmV	42.7 dB	0	0
16	Locked	QAM256	4	477000000 Hz	-1 dBmV	42.9 dB	0	0
17	Locked	QAM256	6	489000000 Hz	-1.3 dBmV	42.5 dB	0	0
18	Locked	QAM256	7	495000000 Hz	-1.6 dBmV	42.5 dB	0	0
19	Locked	QAM256	8	507000000 Hz	-0.8 dBmV	43.1 dB	0	0
20	Locked	QAM256	9	513000000 Hz	-1.4 dBmV	42.6 dB	0	0
21	Locked	QAM256	10	519000000 Hz	-1.5 dBmV	42.5 dB	0	0
22	Locked	QAM256	11	525000000 Hz	-2.3 dBmV	41.9 dB	0	0
23	Locked	QAM256	12	531000000 Hz	-2.7 dBmV	41.9 dB	0	0
24	Locked	QAM256	17	567000000 Hz	-1.9 dBmV	42.5 dB	0	0

Channel	Lock Status	US Channel Type	Channel ID	Symbol Rate	Frequency	Power
1	Locked	ATDMA	1	5120 Ksym/sec	30100000 Hz	51.5 dBmV
2	Locked	ATDMA	2	5120 Ksym/sec	36500000 Hz	49 dBmV
3	Not Locked	Unknown	3	0 Ksym/sec	17300000 Hz	0.0 dBmV
4	Not Locked	Unknown	4	0 Ksym/sec	23700000 Hz	0.0 dBmV
5	Not Locked	Unknown	0	0 Ksym/sec	0 Hz	0.0 dBmV
6	Not Locked	Unknown	0	0 Ksym/sec	0 Hz	0.0 dBmV
7	Not Locked	Unknown	0	0 Ksym/sec	0 Hz	0.0 dBmV
8	Not Locked	Unknown	0	0 Ksym/sec	0 Hz	0.0 dBmV