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SB6183 - internet disconnecting - T3 time out - Timing Synchronization failure

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Regular Visitor

SB6183 - internet disconnecting - T3 time out - Timing Synchronization failure

My internet disconnects multiple times a day. Turning off the modem and turning it back on does not solve the issue. I actually have to unscrew the coax and screw it back in to re-establish the connection. Sometimes it will work for hours, sometimes only minutes. 

 

I've directly connected a laptop to the modem and experienced the same issues. I've also factory reset the modem.

 

Internet was great for about 6 months. I've been dealing with this issue now for over two weeks.

 

SB6183

Asus Dual-band Wireless-AC1900 Gigabit Router

Accepted Solution

Re: SB6183 - internet disconnecting - T3 time out - Timing Synchronization failure

by

The upstream power is too high and may be intermittently fluctuating even higher out of spec. That can cause random disconnects, spontaneous re-booting of the modem, and speed and latency problems.

In a self troubleshooting effort to try to obtain better connectivity / more wiggle room, check to see if there are there 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 big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test

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.


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Connection Expert

Re: SB6183 - internet disconnecting - T3 time out - Timing Synchronization failure

The upstream power is too high and may be intermittently fluctuating even higher out of spec. That can cause random disconnects, spontaneous re-booting of the modem, and speed and latency problems.

In a self troubleshooting effort to try to obtain better connectivity / more wiggle room, check to see if there are there 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 big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test

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.





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Regular Visitor

Re: SB6183 - internet disconnecting - T3 time out - Timing Synchronization failure

Copy that. Thanks for the help EG. I can tell you right now that the drop from the street pole connects to the house, then to two other random smaller coax cables before it enters into my home, where it then splits to the modem and the TV box. I'll try reconfiguring the coax in the way you described, and if I can't make it work, I'll request a tech to come investigate and correct.

Connection Expert

Re: SB6183 - internet disconnecting - T3 time out - Timing Synchronization failure

Good luck with it !




Community Icon
I am not a Comcast employee, I am a paying customer just like you!
I am an XFINITY Forum Expert and I am here to help. For information on the program click here.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark it as an accepted solution!solution Icon
Community Icon
I am not a Comcast employee. I am a paying customer just like you!
I am an XFINITY Forum Expert and I am here to help.
We ask that you post publicly so people with similar questions may benefit.
Was your question answered? Mark it as an accepted solution!solution Icon
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I am not a Comcast employee.

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Mark it as a solution!solution Icon