Community Forum

Own modem not working. Possible signal power issue. Help wanted

Highlighted
Regular Visitor

Own modem not working. Possible signal power issue. Help wanted

Hello:

 

To keep it short the Arris 6190 that I was using for 2.5 years stopped working the moment I signed another contract with xfinity. I bough a brand new 6190 but that one also did not worked. Both times the upstream link didn't come up as bonded.  So I bough Netgear CM700.

 

This Netgear modem shows both upstream and downstrem LED as bonded, it's just the network LED that keeps on blinking. Inretestingly - if the modem is connected and Comcast hasn't activated the modem all LEDs looks good and I'm redirected to some Comcast page to activate the modem. Meaning the Internet works fine with just Comcast website, and DNS works as well.

It's just when modem is activated by Comcast I see network LED blinking non-stop while down/up-stream show bonded. The modem is directly connected to the cable coming from the wall without any splitter or anything else in the way. 3 techs have checked and said signal is good and their own Cisco cable modem works fine.

Either  my modem is blocked or the power level to my suspecion (I guess upstream) is too much. Any help would be greatly appreciated.

 

(LOGS )When Comcast tried to activate the modem:

 

Dec 30 2019 07:22:02

Warning (5)

MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1

Dec 30 2019 07:25:00

Critical (3)

SYNC Timing Synchronization failure - Loss of Sync

Dec 30 2019 07:25:06

Warning (5)

Lost MDD Timeout

Dec 30 2019 07:28:40

Critical (3)

Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out

 

 

Signal status:

 

Frequency start Value

This field below allows you to modify the frequency the cable modem start with its scan during initialization and registration. Enter the new start frequency and restart the cable modem for it to take effect.


Starting Frequency

 
 

Startup Procedure


Procedure

Status

Comment

Acquire Downstream Channel

999000000 Hz

Locked

Connectivity State

Ok

Operational

Boot State

Ok

Operational

Security

Enabled

BPI+

IP Provisioning Mode

Honor MDD

honorMdd(4)

 
   

Downstream Bonded Channels

 

Channel

Lock Status

Modulation

Channel ID

Frequency

Power

SNR

Correctables

UnCorrectables

1

Locked

QAM 256

1

519000000 Hz

0.4 dBmV

40.3 dB

0

0

2

Locked

QAM 256

2

525000000 Hz

0.2 dBmV

40.3 dB

0

0

3

Locked

QAM 256

3

531000000 Hz

0.4 dBmV

40.3 dB

0

0

4

Locked

QAM 256

4

537000000 Hz

0.5 dBmV

40.9 dB

0

0

5

Locked

QAM 256

5

543000000 Hz

0.2 dBmV

40.3 dB

0

0

6

Locked

QAM 256

6

549000000 Hz

0.7 dBmV

40.3 dB

0

0

7

Locked

QAM 256

7

555000000 Hz

0.5 dBmV

40.3 dB

0

0

8

Locked

QAM 256

8

561000000 Hz

1.0 dBmV

40.3 dB

0

0

9

Locked

QAM 256

9

567000000 Hz

1.2 dBmV

40.3 dB

0

0

10

Locked

QAM 256

10

573000000 Hz

1.0 dBmV

40.3 dB

0

0

11

Locked

QAM 256

11

579000000 Hz

1.7 dBmV

40.9 dB

0

0

12

Locked

QAM 256

12

585000000 Hz

1.2 dBmV

40.3 dB

0

0

13

Locked

QAM 256

13

591000000 Hz

1.4 dBmV

40.3 dB

0

0

14

Locked

QAM 256

14

597000000 Hz

1.5 dBmV

40.9 dB

0

0

15

Locked

QAM 256

15

603000000 Hz

1.2 dBmV

40.3 dB

0

0

16

Locked

QAM 256

16

609000000 Hz

1.5 dBmV

40.3 dB

0

0

17

Locked

QAM 256

17

615000000 Hz

1.0 dBmV

40.3 dB

0

0

18

Locked

QAM 256

18

813000000 Hz

2.5 dBmV

40.3 dB

8

0

19

Locked

QAM 256

19

819000000 Hz

3.0 dBmV

40.3 dB

0

0

20

Locked

QAM 256

20

825000000 Hz

3.0 dBmV

40.3 dB

0

0

21

Locked

QAM 256

21

831000000 Hz

3.5 dBmV

40.9 dB

0

0

22

Locked

QAM 256

22

837000000 Hz

3.7 dBmV

40.3 dB

0

0

23

Locked

QAM 256

23

843000000 Hz

3.2 dBmV

40.3 dB

0

0

24

Locked

QAM 256

24

849000000 Hz

3.7 dBmV

41.1 dB

0

0

25

Locked

QAM 256

25

855000000 Hz

3.0 dBmV

39.9 dB

0

0

26

Locked

QAM 256

26

861000000 Hz

2.7 dBmV

39.9 dB

0

0

27

Locked

QAM 256

27

867000000 Hz

2.7 dBmV

39.9 dB

0

0

28

Locked

QAM 256

28

873000000 Hz

2.2 dBmV

39.9 dB

0

0

29

Locked

QAM 256

29

879000000 Hz

2.0 dBmV

40.4 dB

0

0

30

Locked

QAM 256

30

885000000 Hz

1.4 dBmV

39.5 dB

0

0

31

Locked

QAM 256

32

891000000 Hz

1.7 dBmV

39.9 dB

4

0

32

Locked

QAM 256

31

999000000 Hz

1.2 dBmV

38.9 dB

0

0

 
   

Upstream Bonded Channels

 

Channel

Lock Status

US Channel Type

Channel ID

Symbol Rate

Frequency

Power

1

Locked

ATDMA

8

5120 Ksym/sec

17300000 Hz

45.5 dBmV

2

Locked

ATDMA

7

5120 Ksym/sec

23700000 Hz

45.3 dBmV

3

Locked

ATDMA

6

5120 Ksym/sec

30100000 Hz

45.8 dBmV

4

Locked

ATDMA

5

5120 Ksym/sec

36500000 Hz

45.8 dBmV

5

Not Locked

N/A

Unknown

0 Ksym/sec

0 Hz

0.0 dBmV

6

Not Locked

N/A

Unknown

0 Ksym/sec

0 Hz

0.0 dBmV

7

Not Locked

N/A

Unknown

0 Ksym/sec

0 Hz

0.0 dBmV

8

Not Locked

N/A

Unknown

0 Ksym/sec

0 Hz

0.0 dBmV

 
   

Current System Time: Mon Dec 30 20:04:05 2019

 

System Up Time: 01:56:07

 

 

Highlighted
Frequent Visitor

Re: Own modem not working. Possible signal power issue. Help wanted

What you described sounds like what I've been expericing for the past few days.

 

In short:

  • new contract signed, resulting in one of the new speed tiers that's not yet public (200 Mbps, 300 Mbps, 600 or 700 Mbps)
  • using a non-Comcast modem

The answer is that the new speed tiers aren't supposed to go live until tomorrow (Jan 7), but some of the configuration changes were already pushed, so the modems have trouble figuring out what to do with it.

 

The solution is to wait a couple days and try again. The push is supposed to happen tomorrow in stages starting in the morning, so there's no guarantee on when it'll hit your line.

 

Thread describing my issue and troubleshooting: https://forums.xfinity.com/t5/Your-Home-Network/can-t-connect-to-internet-since-halfway-through-cont...

Highlighted
Frequent Visitor

Re: Own modem not working. Possible signal power issue. Help wanted

From Comcast tech who just visited:

 

Other modems have resumed operation, but SB6190 still cannot connect, likely due to firmware issues. I'm currently connected via a Motorola MB7621 I bought a few days ago.

 

The "solution" is to raise the issue with Arris support, so they hopefully acknowledge it and provide a firmware update to Comcast ASAP. Please see https://forums.xfinity.com/t5/Your-Home-Network/can-t-connect-to-internet-since-contract-renewal/m-p... for more detail.

Highlighted
Regular Visitor

Re: Own modem not working. Possible signal power issue. Help wanted

Hi there:

 

Really appreciate your reply. I do get some satisfaction that I'm not alone 🙂

Today I'm going to try again using my Netgear 700 modem. Not sure about firmware - because it's the ISP who controlls what firmware the modem should be using as only they control it.  and I guess that is the protocol.

I'm curious if you were suggested by the tech or the Xfinity customer support to get any signal for uplink or downlink changed or anything else?

 

I'll share my experience later by tonight or tomorrow.

 

Thanks again!

Highlighted
Frequent Visitor

Re: Own modem not working. Possible signal power issue. Help wanted

Your modem power level and SNR both look fine -- much better than mine, in fact.

 

My SB6190 is still refusing to connect, and I'm not having any luck with ARRIS customer support. Given that I've had the SB6190 for ~3 years, I've more than recovered its cost through the modem rental fee savings. I'll probably write off the SB6190 as a lost cause and use the Motorola MB7621 instead.

 

I hope you have better luck than I.

Highlighted
Regular Visitor

Re: Own modem not working. Possible signal power issue. Help wanted

Hia there:

 

Based on your feedback I reached out to xfinity customer care and my Netgear CM700 was activated under a minute!

 

This is totally biazzare how come signing new contract caused a modem to stop working and not just that the even the brand new one didn't work. I returned the Comcast rented modem and want to continue on my Netgear modem.

 

Thanks again for sharing your feedback. your response was far more helpful than the help from Xfinity!

 

Good luck with your Motorola modem.

 

cheers.

 

Happy  surfing!

Highlighted
Regular Visitor

Re: Own modem not working. Possible signal power issue. Help wanted

quick note:

 

My 2.7 year Arris 6190 still showed issues with upstream, while downstarem looked good. Netgear looked good all through. hth!

Highlighted
Frequent Visitor

Re: Own modem not working. Possible signal power issue. Help wanted

Thanks. My MB7621 is happily humming along, and I've returned the Comcast rental.

 

ARRIS customer service grudgingly agreed to take my report into consideration, but I don't expect much to come out of it, at least not in the short term where it'd matter. I plan to keep the SB6190 around as a backup, since it does have more downstream channels than the MB7621, and may one day become useful again if they fix the issue.

 

I guess the important part of we're all back online!