Internet keeps dropping over 10 times a day. Modem log gives "No Ranging Response received - T3 time-out" errors

@user_83nhzb 

Please redact all of the CM MAC and the CMTS MAC addresses from your error log entries for your privacy. They are considered to be personal information. The posting of personally identifiable information is a violation of their forum guidelines. The forum bot will not allow your post to be seen publicly. It flagged your post as "Private".

That said. The upstream power is on the high side (it's already out of spec on channel #5) and it may be intermittently fluctuating even higher to out of spec levels. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, latency problems, and the un-bonding of channels.

In an effort to try to obtain better connectivity / more wiggle room, check to see if there are 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 from Home Depot, Target, Wal-Mart, etc. Splitters should be swapped with known to be good / new ones to test.

Also check the coax cable for any damage such as cuts, nicks, abrasions, kinks, sharp bends, etc.

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.

Good luck with it !

Quite welcome ! I made your post publicly viewable again. Please post back about how things go, thanks.

Still not much wiggle room there... Live with it for awhile and see.

Update: no more drops so far. A Xfinity tech came over and added a connection box for the outdoor connector and filter. Channel #5 power drops to 49. Still good so far.

49.... I'll state this again. Still not much wiggle room there... Live with it for a while and see. Hope things hold up for you ! Good luck !

My pleasure !