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user_4g59b9
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Monday, May 5th, 2025

Consistent T3 time-out in modem logs

Consistent T3 time-out in modem logs

Problem

I believe this line sums up the problem. Found these in modem event log

2025-5-5, 12:24:33 Critical (3)  16 consecutive T3 timeouts while trying to range on upstream channel 3;CM-MAC=REDACTED;CMTS-MAC=REDACTED;CM-QOS=1.1;CM-VER=3.0;

Network environment

Feel free to ask questions

Modem NETGEAR CM500-100NAS
Gateway UniFi UCG-Max
Access Point UniFi U7-Pro

Customer Information

DM for information

Question

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Updated 

3 months ago

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EG

Expert

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112.2K Messages

3 months ago

Are you actually experiencing any connection problems, or are you just focusing on the error log entries ? 

What do the modem's signal status values look like ?

Please copy all of the text in its entirety of the *Downstream Power Levels*, the *SNR's* (Signal to Noise Ratios), and the *Upstream Power Level* numbers and paste them into your next post.

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EG

Expert

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112.2K Messages

3 months ago

The downstream power is a tad on the high side but that may not be a problem. The upstream has only one channel locked in. There should be around three to six. This is typically caused by noise ingress into the line(s) / a connection impairment somewhere. First. Try power cycling the modem one more time. This can sometimes help to pull a new / cleaner set of channels. Please post back with how that goes.

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user_4g59b9

9 Messages

Same problem. Since the modem takes minimum 5-10 minutes just to get a lock and provision WAN to its Ethernet output I'm assuming the issue lies beyond CPE.

(edited)

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3 months ago

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user_4g59b9

9 Messages

Please escalate this to a local team.

Washington Township, NJ 07853

(edited)

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3 months ago

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user_4g59b9

9 Messages

3 months ago

@EG any updates to share? It took me 3 tries to download a complete Windows ISO today. Speeds are "ok" considering the current modem hardware, but service quality is questionable at best.

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XfinityJamesC

Official Employee

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2.3K Messages

Greetings, @user_4g59b9! Thanks so much for taking a moment out of your busy day to leave a post on our community forum. I'm sorry to hear you're having issues with your connection, but you have definitely come to the right place for assistance.

 

If you could send our team a direct message with your full name, the name listed on the account (if different), and the service address associated with your account, I'd be more than happy to look into this for you.

 

To send a Direct Message, please click on the “Direct Message” icon in the top-right corner of the screen, next to the bell icon, click the "New message" (pencil and paper) icon, then type or select "Xfinity Support". Type your message in the text area near the bottom of the window and press Enter to send your message and initiate a live session.

I am an Official Xfinity Employee.
Official Employees are from multiple teams within Xfinity: CARE, Product, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Please, mark a reply as the Accepted Answer.tick

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3 months ago

EG

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112.2K Messages

3 months ago

@user_4g59b9 @XfinityJamesC 

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.

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user_4g59b9

9 Messages

@EG​ The issue was at the pole, outside the home - fixed by technician. Thanks for following up 😎

(edited)

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3 months ago

EG

Expert

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112.2K Messages

@user_4g59b9​ For curiosity, would you please post what the signal values look like now.

I am not a Comcast Employee.
I am a Customer Expert volunteering my time to help other customers here in the Forums.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Please mark an Accepted Answer!tick

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3 months ago

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