T3 timeout - Repeated Internet Disconnections Throughout the Day

Below is the event log from my Netgear CM1000v2 modem. My home internet connection has been experiencing repeated drops multiple times per day.

Time	Priority	Description
2025-03-28, 05:42:39	Notice (6)	CM-STATUS message sent. Event Type Code: 8; Chan ID: 1 2 5 11; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: N/A.;CM-MAC="Personal_info";CMTS-MAC="Personal_info";CM-QOS=1.1;CM-VER=3.1;
2025-03-28, 05:42:32	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC="Personal_info";CMTS-MAC="Personal_info";CM-QOS=1.1;CM-VER=3.1;
2025-03-28, 05:42:31	Critical (3)	No Ranging Response received - T3 time-out;CM-MAC="Personal_info";CMTS-MAC="Personal_info";CM-QOS=1.1;CM-VER=3.1;
2025-03-28, 05:42:30	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC="Personal_info";CMTS-MAC="Personal_info";CM-QOS=1.1;CM-VER=3.1;
2025-03-28, 05:42:30	Critical (3)	No Ranging Response received - T3 time-out;CM-MAC="Personal_info";CMTS-MAC="Personal_info";CM-QOS=1.1;CM-VER=3.1;
2025-03-28, 05:42:30	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC="Personal_info";CMTS-MAC="Personal_info";CM-QOS=1.1;CM-VER=3.1;
2025-03-28, 05:42:29	Critical (3)	No Ranging Response received - T3 time-out;CM-MAC="Personal_info";CMTS-MAC="Personal_info";CM-QOS=1.1;CM-VER=3.1;
2025-03-28, 05:42:28	Critical (3)	16 consecutive T3 timeouts while trying to range on upstream channel 5;CM-MAC="Personal_info";CMTS-MAC="Personal_info";CM-QOS=1.1;CM-VER=3.1;
2025-03-28, 05:42:28	Critical (3)	Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC="Personal_info";CMTS-MAC="Personal_info";CM-QOS=1.1;CM-VER=3.1;
2025-03-28, 05:42:26	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC="Personal_info";CMTS-MAC="Personal_info";CM-QOS=1.1;CM-VER=3.1;
2025-03-28, 05:42:25	Critical (3)	No Ranging Response received - T3 time-out;CM-MAC="Personal_info";CMTS-MAC="Personal_info";CM-QOS=1.1;CM-VER=3.1;
2025-03-28, 05:42:25	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC="Personal_info";CMTS-MAC="Personal_info";CM-QOS=1.1;CM-VER=3.1;
2025-03-28, 05:42:24	Critical (3)	No Ranging Response received - T3 time-out;CM-MAC="Personal_info";CMTS-MAC="Personal_info";CM-QOS=1.1;CM-VER=3.1;
2025-03-28, 05:42:23	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC="Personal_info";CMTS-MAC="Personal_info";CM-QOS=1.1;CM-VER=3.1;
2025-03-28, 05:42:22	Critical (3)	16 consecutive T3 timeouts while trying to range on upstream channel 2;CM-MAC="Personal_info";CMTS-MAC="Personal_info";CM-QOS=1.1;CM-VER=3.1;
2025-03-28, 05:42:22	Critical (3)	Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC="Personal_info";CMTS-MAC="Personal_info";CM-QOS=1.1;CM-VER=3.1;
2025-03-28, 05:41:14	Critical (3)	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC="Personal_info";CMTS-MAC="Personal_info";CM-QOS=1.1;CM-VER=3.1;
2025-03-28, 03:25:12	Notice (6)	CM-STATUS message sent. Event Type Code: 24; Chan ID: 48; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC="Personal_info";CMTS-MAC="Personal_info";CM-QOS=1.1;CM-VER=3.1;
2025-03-28, 03:22:34	Notice (6)	CM-STATUS message sent. Event Type Code: 16; Chan ID: 48; DSID: N/A; MAC Addr: N/A; OFDM/OFDMA Profile ID: 3.;CM-MAC="Personal_info";CMTS-MAC="Personal_info";CM-QOS=1.1;CM-VER=3.1;

Frequency start Value

This 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

<tabindex=-1>Startup Procedure</tabindex=-1>

Procedure	Status	Comment
Acquire Downstream Channel	651000000 Hz	Locked
Connectivity State	OK	Operational
Boot State	OK	Operational
Security	Enable	BPI+
IP Provisioning Mode	Honor MDD	IPv6 only

<tabindex=-1>Downstream Bonded Channels</tabindex=-1>

Channel	Lock Status	Modulation	Channel ID	Frequency	Power	SNR / MER	Unerrored Codewords	Correctable Codewords	Uncorrectable Codewords
1	Locked	QAM256	44	651000000 Hz	-1.9 dBmV	41.5 dB	3747005213	47370	26244
2	Locked	QAM256	17	483000000 Hz	-2.8 dBmV	41.1 dB	3738281848	65044	37934
3	Locked	QAM256	18	489000000 Hz	-2.9 dBmV	41.2 dB	3686609660	68161	39732
4	Locked	QAM256	19	495000000 Hz	-2.7 dBmV	41.2 dB	3687097677	77524	45060
5	Locked	QAM256	20	507000000 Hz	-2.1 dBmV	37.1 dB	3738316147	63343	35767
6	Locked	QAM256	21	513000000 Hz	-2.1 dBmV	39.3 dB	3738351205	61351	34417
7	Locked	QAM256	22	519000000 Hz	-2.1 dBmV	41.1 dB	3738355507	62277	37268
8	Locked	QAM256	23	525000000 Hz	-2.1 dBmV	41.0 dB	3738377560	60660	34280
9	Locked	QAM256	24	531000000 Hz	-2.0 dBmV	41.2 dB	3738397107	59861	33710
10	Locked	QAM256	25	537000000 Hz	-2.0 dBmV	41.4 dB	3738438006	57316	32377
11	Locked	QAM256	26	543000000 Hz	-2.0 dBmV	41.4 dB	3738464182	57486	32528
12	Locked	QAM256	27	549000000 Hz	-2.1 dBmV	41.2 dB	40293509	57485	31263
13	Locked	QAM256	28	555000000 Hz	-2.1 dBmV	41.1 dB	3738494188	56908	31635
14	Locked	QAM256	29	561000000 Hz	-1.9 dBmV	41.2 dB	3738511274	56381	30617
15	Locked	QAM256	30	567000000 Hz	-2.0 dBmV	41.4 dB	3738586608	52107	29967
16	Locked	QAM256	31	573000000 Hz	-2.1 dBmV	41.4 dB	3738604667	54392	30177
17	Locked	QAM256	32	579000000 Hz	-2.2 dBmV	41.2 dB	3738603082	63022	32209
18	Locked	QAM256	33	585000000 Hz	-2.4 dBmV	40.9 dB	3738634650	49050	28500
19	Locked	QAM256	34	591000000 Hz	-2.2 dBmV	41.2 dB	3738657535	51310	27348
20	Locked	QAM256	35	597000000 Hz	-2.0 dBmV	40.9 dB	3738686326	47333	27009
21	Locked	QAM256	36	603000000 Hz	-1.8 dBmV	40.1 dB	3738720605	47536	27093
22	Locked	QAM256	37	609000000 Hz	-1.8 dBmV	40.7 dB	3738718320	46527	26573
23	Locked	QAM256	38	615000000 Hz	-1.9 dBmV	41.5 dB	3738750571	43262	25379
24	Locked	QAM256	39	621000000 Hz	-2.0 dBmV	41.5 dB	3738771857	44300	25330
25	Locked	QAM256	40	627000000 Hz	-2.1 dBmV	41.4 dB	3738794267	44893	26234
26	Locked	QAM256	41	633000000 Hz	-1.8 dBmV	41.6 dB	3738817400	42423	25390
27	Locked	QAM256	42	639000000 Hz	-1.7 dBmV	41.5 dB	3738828607	41539	24939
28	Locked	QAM256	43	645000000 Hz	-1.7 dBmV	41.7 dB	3738861462	40949	23962
29	Locked	QAM256	45	681000000 Hz	-1.8 dBmV	41.7 dB	3738921125	39410	22433
30	Locked	QAM256	46	687000000 Hz	-1.8 dBmV	41.6 dB	3739011375	39385	22564
31	Locked	QAM256	47	693000000 Hz	-2.0 dBmV	41.6 dB	3738979859	35947	20655
32	Not Locked	Unknown	0	0 Hz	0.0 dBmV	0.0 dB	0	0	0

<tabindex=-1>Upstream Bonded Channels</tabindex=-1>

Channel	Lock Status	Modulation	Channel ID	Frequency	Power
1	Locked	ATDMA	1	10400000 Hz	48.0 dBmV
2	Locked	ATDMA	2	16400000 Hz	47.5 dBmV
3	Locked	ATDMA	3	22800000 Hz	47.5 dBmV
4	Locked	ATDMA	4	29200000 Hz	47.3 dBmV
5	Locked	ATDMA	5	35600000 Hz	47.0 dBmV
6	Locked	ATDMA	11	40400000 Hz	46.5 dBmV
7	Not Locked	Unknown	0	0 Hz	0.0 dBmV
8	Not Locked	Unknown	0	0 Hz	0.0 dBmV

<tabindex=-1>Downstream OFDM Channels</tabindex=-1>

Channel	Lock Status	Modulation / Profile ID	Channel ID	Frequency	Power	SNR / MER	Active Subcarrier Number Range	Unerrored Codewords	Correctable Codewords	Uncorrectable Codewords
1	Locked	0, 1, 2, 3	48	850000000 Hz	-1.8 dBmV	39.5 dB	1108 ~ 2987	34146865467	32690217011	32845
2	Not Locked	0	0	0 Hz	-2.2 dBmV	0.0 dB	0 ~ 4095	0	0	0

<tabindex=-1>Upstream OFDMA Channels</tabindex=-1>

Channel	Lock Status	Modulation / Profile ID	Channel ID	Frequency	Power
1	Not Locked	Unknown	0	0 Hz	0 dBmV
2	Not Locked	Unknown	0	0 Hz	0 dBmV

Current System Time: Fri Mar 27 22:26:07 2025

System Up Time: 499:54:02

Responses

XfinityEricB

Official Employee

•

2K Messages

4 days ago

user_iesv4k Thanks for reaching out with you timeout concerns, and for the current logs. Let me see if I can locate what is causing the problem to fix it for you.

Can you send us a direct message with your full name, name of account holder (if different), and service address please?

To send a "Direct Message" to Xfinity Support:

Click "Sign In" if necessary

Click the "Direct Messaging" icon (speech bubble)

Click the "New message" (pencil and paper) icon

The "To:" line prompts you to "Type the name of a person". Instead, type "Xfinity Support" there

As you are typing a drop-down list appears. Select "Xfinity Support" from that list

An "Xfinity Support" graphic replaces the "To:" line

Type your message in the text area near the bottom of the window

Press Enter to send it

EG

Expert

•

109.5K Messages

4 days ago

@user_iesv4k @XfinityEricB

Please circle back here and post any possible solutions for the issue here in these open public forums so that all readers here may benefit from the exchange / info. This is in keeping with the spirit for which these public help forums were originally intended. Thank you.

Your Home Network

user_iesv4k

T3 timeout - Repeated Internet Disconnections Throughout the Day

XfinityEricB

EG

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