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Arris WBM760A -> No Solid "Online" Light

Frequent Visitor

Arris WBM760A -> No Solid "Online" Light

Hello,

 

I've been trying a few days to get online but with no success.  Even with nothing but power and cable plugged into the modem it never gets a solid "online" light...

 

Any pointers would be great as I'm not sure if the problem is something with my setup or something beyond my control (e.g. cable lines coming into house etc...)

 

Here is my Cable Modem Info:

ARRIS DOCSIS 3.0 Touchstone WideBand Cable Modem
HW_REV: 3
VENDOR: Arris Interactive, L.L.C.
BOOTR: 1.2.1.25
SW_REV: 7.1.98
MODEL: WBM760A

Firmware Name: TS070198_071510_WBM_7

Firmware Build Date: Thu Jul 15 11:38:51 EDT 2010

 

Here is the behavior pattern that I observe with my laptop plugged in to monitor modem status:

1)  Establish Downstream ->DS Power Level: 8.39 dBmV & SNR: 38.61dB

2)  Establish Upstream -> US Power Level: 45.25 dBmV

3)  CM Status goes to:  DHCPV6_IN_PROGRESS

4)  I get an error in the log:

DHCP FAILED - Critical field invalid in response;CM-MAC=00:xx:xx:xx:xx:xx;CMTS-MAC=00:01:5c:22:64:0c;CM-QOS=1.1;CM-VER=3.0;

 

The whole thing just repeats over and over and the cable modem never get successfully completes DHCP.   Sometimes it doesn't start completely over but the US or DS light start blinking again and it has to resysnc before the online light begins to blink again -> but online *never* goes solid and I have never received an comcast IP address on my laptop...

 

Detailed DHCP Log:

CM DHCP LOG 4
Thu, 01 Jan 1970 00:58:17 +0000
Interface: wan0
Message type: solicit
Client ID: 00:03:00:01:00:xx:xx:xx:xx:xx
Server ID: 00:03:00:01:00:xx:xx:xx:xx:xx
Preference: -1
IA_NA/IA_PD count: 1
IA details:
IA type: 3, IA ID: -785043292, t1: 0, t2: 0, IA addr count: 1
IA prefix addr details:
Stateful addr: ::, Pltime: 0, Vltime: 0
Options buffer: len: 72, details:
Option: [1]client ID, option len: 10
Option: [3]identity association, option len: 40
Option: [14]rapid commit, option len: 0
Option: [8]elapsed time, option len: 2

 

I've hooked the modem up directly to the incoming cable line and notice that the DS Power level increased to about 13.5dBmV and the US Power level drops to 42.0dBmV, but still no connection established.  There is some damage in the incoming line with about 1/4"  of the rubber exterior peeled off and some of the shield is damaged, but it doesn't seem like there is any short between the shield and the center co-ax.

 

I have no router in the loop, only connected directly to various laptops.  I've tried it in Windows 7, Ubuntu 9.10 Linux Kernel Version 2.6.31-10-generic, and on an older Mac laptop.  I did notice that I have to manually set the Ethernet port to 100MB Full Duplex in order to get a link light on the cable modem as it doesn't seem to "auto negotiate"...

 

Finally, I purchased the modem through Amazon.com marketplace as such:

"Included are:New Power supply, New Ethernet cable,Cable modem. All cable modems are individually tested and guaranteed to work. We stand behind our product with a 100 % money back guarantee."

 

I hope that is enough information, if not I can run some more tests or show other modem status etc...  Thanks!

Diamond Problem Solver

Re: Arris WBM760A -> No Solid "Online" Light

It should achieve block sync with the system regardless but have you yet tried having it provisioned for service by them ?? If it is listed in their database as being missing /stolen then it may not work.

 

I never recommend buying modems from Amazon or E-Bay if they are used.

Frequent Visitor

Re: Arris WBM760A -> No Solid "Online" Light

Hrmm... I tried phone support 3 different times and tried all of the unplug/replug stuff etc.  They tried to reset the modem remotely etc but they told me they can't see it.  I gave the CMAC every time and no one mentioned anything about a "database" or similar issue... 

 

I'll call them up and ask if its stolen and resold to me or something, that would be lame...  Thanks for the heads up...  I'll report back here asap..

Diamond Problem Solver

Re: Arris WBM760A -> No Solid "Online" Light

If they "can't see it" you may have to give them the MAC address and the serial number.

Frequent Visitor

Re: Arris WBM760A -> No Solid "Online" Light

I called comcast phone support and asked specifically if my modem appears in a database of stolen devices.  They verified the make/model, serial number, and CMAC of the device are all properly registered to my account.

 

They tried all the remote stuff again and the modem never shows up as "online" to them either.  It sounds like I have a tech coming out to perform a "professional install" though this particular phone tech suggested that it might be an issue with wiring not being properly hooked up outside of the house.

 

I called the landlord and the previous two tennets had no problems with comcast in the same location...*shrug*

 

I wish I had another modem just to try it out... Thanks for any other tips, as I'm skeptical about the line being bad as it seems to have decent signal levels...

 

 

Diamond Problem Solver

Re: Arris WBM760A -> No Solid "Online" Light

Good luck with it ! Smiley Happy

Frequent Visitor

Re: Arris WBM760A -> No Solid "Online" Light

The tech came out and put in a new modem, the new modem works fine...  No idea why the old modem didn't, but I will try to return it for a refund...

 

Thanks

Diamond Problem Solver

Re: Arris WBM760A -> No Solid "Online" Light

Thanks for the feedback.