CM1000 SYNC timing Synchronization failure

Question

I have had a CM1000 with COX preferred 150 Mbps for about two years with no issues. Recently all of the coax in my house to the street was replaced after my modem was not able to establish a connection and water was discovered in the coax cable going all the way to my Modem. Now that the cables have been replaced my modem can still not establish an internet connection. When I reboot the unit the download light goes solid green the upload light goes solid green and the internet light begins to blink green slowly. Shortly after that all lights except for the power LED turns off and then the download light goes solid green and the upload light blinks green. This remains until I restart the device starting this over again.

In the even logs I get the following failures:
SYNC Timing Synchronization failure
Lost MDD Timeout
Honoring MDD
DHCP WARNING
TLV-11 - unrecognized OID
REG RSP not received
Started Unicast Maintenance Ranging
REG RSP not received
T6 Timeout and retries exceeded
No Ranging Response received
B-INIT-RNG Failure

Current Info
HW 2.02
FW V6.01.07

Please help before I light this crap on fire.

FURRYe38 · Answer

Have the ISP check the signal and line quality UP to the modem. Be sure the ISP provisions the modem correctly.
Be sure there are no coax cable line splitters in the between the modem and ISP service box.
Be sure your using good quality RG6 coax cable up to the modem.
Be sure to power OFF the modem for 1 minute them back ON.
https://community.netgear.com/t5/Cable-Modems-Routers/General-info-and-Troubleshooting-for-Cable-Modems/m-p/1530376#M12853

plemans · Answer

You're caught in a catch-22. the modem could have failed from the water in line. Its rare but it could have happened. since you're out of warranty your options are:1. have them check the line again2. replace the modem with a new one.3. rent a modem for a month.&nbsp;&nbsp;You could try buying a new one from somewhere with a generous return policy. If it doesn't fix the issue and its still a line issue, then when its working, you could always try the old one/return the new one if it works.&nbsp;

CL4880 · Answer

Thank you for the information.The ISP supervisor is supposed to contact me tomorrow about replacing the modem since the tech said the line is good. Hopefully they do what is right and get me a new modem since it worked great until this issue happened.

CL4880 · Answer

So I had a technician out today and he confirmed after replacing all the lines that the signal and line quality UP to the Modem is good. All of the cable is brand new as of today Cat6. Tried the restart with waiting 10 minutes between off and on but problems persist. How can I make sure that the ISP is provisioning for the Modem properly?

plemans · Answer

You can't really. I've heard of water in the line actually causing enough feedback in coax to cause issues with a modem. I've never experienced it.

Did the technician actually attach a modem and test it or just their testing device?

any old modems laying around to check if it is a modem failure?

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CM1000 SYNC timing Synchronization failure

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