Question about Arris SB5100 SURFboard DOCSIS 2.0 Cable Modem (50120900100)

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The 3 lights blink on and then off and on and then off etc.

My three modem lights (receive, send, online) were fine yesterday but today they suddenly all turned off except for the power light and one by one each light blinks on, and then once they all blink on, after 1 or 2 minutes they all turn off and start to blink on. So I can get to the internet one minute and the next minute I can't and it's really annoying. Once I forgot to pay my internet bill so and my modem did something similar but it didn't let me go onto the internet at all. And the internet bill is paid so I know that isn't the problem again. and even when I turn the modem off, the lights still blick on and off. Can anyone help me?

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Re: The 3 lights blink on and then off and on and then...

Try and restore your computer by clicking on start all programs, accessories, system tools then system restore, restore it back for a few days or a week even try that

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I have a motorola sb4200 cable modem that was working just fine until 3 days ago the power light is steady and the send and receive lights alternative in blinking and being steady none of the other lights...

Thank you for the detailed information. Not having internet can be frustrating! If the "Online" light is not turning on, that means it is not obtaining an IP address from your internet service provider. Since the "send" and "receive" lights are blinking, this means the coaxial cable (Tv cable) is screwed in.

I would suggest finding a phone number for your internet service provider to assist you further. There may be a service outage in your general area, or there may be a localize issue. They may have to go through troubleshooting with you over the phone, so you may have to unplug the modem, and maybe even bypass the Netgear router to troubleshoot with them. If the issue cannot be resolved over the phone, they may need to send out a repair man to resolve your issue.

May 26, 2011 | Arris SURFboard SB4200 Modem

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Yesterday had Cable Internet hooked up at new house--when done modem had all lights green, and wireless router connected and worked fine. Now router won't connect to Internet, and USB connection direct to...

Sounds like a problem with your cable connection. Check your coaxial cable, and the splitter from where the cable enters your home. The tech will use a signal meter to measure the quality of your cable, and then replace the wiring if necessary.

Jan 04, 2011 | Motorola Modems

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My internet connection does not work. I can't connect to internet. My modem blinks but it seems it can not find anything to connect to it. It used to work for a few months but suddenly without any reason...

turn the computer off and unplug the modem for few seconds (15) then reconect the modem and let it start all the lights
about (20s) then turn the computer on.
if still cannot connect call your ISP

Aug 20, 2010 | Arris SURFboard SB5120 Modem

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Power, Receive, Send flashes, No online light or the rest. Help?

Throw it away or send it to Motorola they get very HOT and this causes failure its common in routers and modems

Sep 21, 2009 | Arris SURFboard SB4200 Modem

1 Answer

Online light blinking

change the last four digits on the mac

Jul 28, 2009 | Arris SURFboard SB4200 Modem

1 Answer

I have the sbg900. It suddenly quit working. I get the green power light and orange wireless light. The recieve light blinks slowly. The send, online, and activity lights do not light at all. The wireless...

Best to call up the cable company and go thru the phone may just find that they're having trouble in your area...
They can also send a reset signal to your modem too.
Give em a call..

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No connectivity; constant blinking LED lights "Receive" and "Send"

Or you didn't pay your subscription on time and the ISP disabled your cable modem to send user traffic over the cable network. When both Send and Receive lights are blinking that is a visual aid that the modem is working fine, but the ISP disabled its access to the network (unpaid bill, legal issues, etc.)

May 17, 2009 | Arris SURFboard SB5101 Cable Modem

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Receive activity and send lights are blinking. power light is on. and online is off

try to unplug it and the cable for a few minutes, then replug it and see if that helps.

Jul 27, 2008 | Arris SURFboard SB4200 Modem

1 Answer

Receive, send, and activity lights are all blinking but online light is off

Power Cycle the modem if the 4 lights do not go solid you would want to contact your cable provider to ensure signal is being received properly to modem.

Jul 27, 2008 | Arris SURFboard SB4200 Modem

1 Answer

Im having problems getting my modem to get online. The light wont come on. All but the online light come on. The online light blinks then all the lights go off except the power light, and the receive...

Your modem is not synching. It could be a number of possibilities, and you're going to have to do some troubleshooting to narrow it down.
  • Verify that your AC, Cat 5, & ethernet cables are connected securly
  • Verify that your modem is not in "standby" mode
  • Power cycle your modem
  • Try a different cable outlet
  • Call your ISP to make sure your modem is provisioned and your service is set up for cable internet.

Nov 06, 2007 | Arris SURFboard SB5120 Modem

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