3 Answers

Not working the modem internet light is flash which is the only light that is on the others are off

Posted by on

3 Answers

  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 4 Answers
Re: not working

Either there is no signal to the modem. or the modem is bad. 1 blinking light says it is looking for the downstream signal. Has cable company disconnected you? Can you try modem on different outlet that maybe has active signal for your cable box. Is there any cheap radio shack (store bought splitters inline) these won't pass the channels that some modems work on.

Posted on May 02, 2008

Re: not working - RCA DCM425 DIGITAL CABLE MODEM (RCADCM425) Modems


Posted on Sep 19, 2007

Re: not working

I have no idea why this happens, but unplugging it for a while and reseting it seem to help.

Posted on Sep 16, 2007

Add Your Answer

0 characters

Uploading: 0%


Complete. Click "Add" to insert your video. Add


3 Points

Related Questions:

1 Answer

What happen when a adsl line work with a phone but not with a router

The phone line does two jobs. Voice phone which is what it was originally used for and ADSL modem which works at a high audio frequency.
Somewhere between the phone socket and the modem should be a filter splitter. One part goes to the phone and the other to the router. Make sure you have that.
The modem will have a power light and several additional lights. Assuming the power light is on we are interested in two of them; The ADSL light and the Internet light. When you switch the modem on you should first see the power light flash then go solid. Then the ADSL light will flash and then this should go solid. If this light does not come on then you have not plugged the phone wire in properly. If this light just keeps flashing slowly then the modem can't see an ADSL signal on the phone line. If you have a spare router you could try it and see if the ADSL light goes solid on that.
If the ADSL light is fine then the modem has locked onto the signal on the phone line, sync'ed. If not then this is the problem you must solve. Ask your ISP if service is set on your line.
The next light is the Internet light, this maybe a symbol like an i or a world. This light will begin flashing then go solid. It will flash with Internet traffic. This means you have Internet, as far as the modem is concerned. If this light does not stay on then your ADSL account name and password maybe wrong. You can correct this but that's a different question you need to ask.

Feb 18, 2015 | D-Link Dsl-2750b Adsl2 Verizon N Wireless...

1 Answer

I have a Motorola SB 5120 modem the P/C light is always flashing .At time I can't get on Wi-Fi from my I Phone or my desk in my sons room, and other time i can.What is going on or do I need another...


The flashing lights (espicially the Internet light) are normal, they indicate activity (Power, LAN, Broadband, Internet).

Some modems suffer from signal interference from other wireless devices in your home and neighbourhood.

Sometimes the problem may be a signal deadspot in your home to do with unseen metal, pipes, wiring or some other aspect of the buildings architecture.

If your modem has a detachable aerial that crews and unscrews, then it might be possilble to buy a larger more powerful booster aerial for it (take the old aerial to the store with you to ensure compatibilty of the screw fitting) that will give you a better signal.

The modem does not have to be sited near a phone socket. Consider resiting the modem to a good central point where everyone gets a good signal, by buying and using Male to Female power cord extensions and Modem cable extensions.

Ensure that your internet connection is enctypted with a private network key and protected by a password, so that neighbours cannot pirate your internet connection and thus use up your bandwidth and slow down or degrade your signal.

I hope this helps.

Aug 25, 2011 | Arris SURFboard SB5120 Modem

1 Answer

Modem is not connecting to internet. "ACT" light

Call your Internet provider.

Feb 13, 2011 | Modems

1 Answer


So that means its working well and connected to the ISP' server. What is your connection? Is it ADSL?
First make sure that all light have the color of green. If they are Flashing with color RED that means the property associated with the light is having a failure.
Here are the description of Colors and Lights.
Modem Light state: Unlit Flashing Red Flashing Green Steady Green
Power Light
Modem is not getting power - no light Modem has failed POST - Red Power is on - Steady Green
Ethernet (2nd Light)
No Ethernet link detected - No light Problem with ethernet port or cable - Flashing Green Modem has detected a successful link to a PC or router - Steady Green
DSL (3rd light)
ADSL sync signal is not detected - Red Modem is trying to synchronize. - Flashing Green Modem has ADSL sync and is ready for PPPoE session traffic - Steady Green.
Internet (4th light)
Modem has given up or isn't configured to initiate the PPPoE session - No Light PPPoE initiation has failed or PPPoE has been terminated. - Red Initiating a PPPoE session to Internet - Flashing Green. Modem is ready for Internet traffic - Steady Green.
Note: This light sometimes not working even if the connection initiated.
Normal DSL traffic flow - Flashing Green. Steady traffic flow - Steady Green.
Solving problems.
Case1: You have to connect your machine to the Modem Via the Network cable. Plug the other side of the cable to your Machine. (Not the modem port. Network card port.). Case2: You have to make sure that you have installed the Network Card drives. To check that you have to use Device Manager. Follow these steps. Hit Windows key with R In the "Run" box type devmgmt.msc In the right hand side check whether the network card is installed. If it has a yellow exclamation mark or a mark with red that means you haven't either installed or its having a device/driver problem.
Case3: If its fine then what you have to do is to check your network settings. Heres how: Since you haven't specified the Operating System I m including the Windows XP method here. Not much difference in other Operating Systems as well.
  • Get the Control Panel.
  • Go to Network and Internet Connections.
  • Go to Network Connections.
  • Check the Local Area Connection.
  • Right Click and check "Status".
  • If it says connected
  • Check the Duration and Speed(100 or 1000Mbps).
  • If the settings are fine go to "Support" Tab.
  • Check whether the Machine has received an IP Address. Which is often in the range of for Siemens Modems/Routers.
  • If you see an IP Address which starts from your network card was unable to pick an IP Address from the DHCP router which runs in the modem. (If you run a DHCP in the machine you have to configure to stop leasing IP Addresses to your machine from the Router/Modem. You can try the "Repair" button below and it will try to Release and Renew your IP. If it fail either you have a problem with your network card or Modem/Router (Could be the cable also).
  • If you still see the IP Address which starts with 192.168 the connection with your Modem is fine.
  • Next: Right Click on the Local Area Connection again.
  • Go to "Properties".
  • Double Click on "Internet Protocol (TCP/IP).
  • Check the settings.
  • The settings should be "Obtain IP Addresses Automatically" and "Obtain DNS Server Address Automatically". (But if you know the router's/Modem's IP Address you can configure it and you can give a "Static IP" to your PC as well. It must not be the Router's / Modem's IP and must be in th SAME SUBNET. If router uses you can assign it as
  • Then Apply the Settings and go to the "Status" again and then click on "Details".
  • Except Wins Server all others must be populated with values in 192.168 range. Check the "Default Gateway" Setting. Its very important that you have pointed the machines Default Gateway to the Router/Modem.
  • Final Check:
  • Go to the "Internet Protocol (TCP/IP) again and click on "Advanced".
  • Check IP Settings (first tab) too make sure DHCP is enabled on you machine.
  • Go to "Options" tab and Check TCP/IP Filtering. Click on properties and make sure that the Filtering is not enabled. If it enabled make sure your network adapter Permits all routers traffic in to the machine.
By following these options will let you surf the internet.
Check for the behaviors of indicators as well.
Case 3 :Browser settings
In the Internet Explorer go to: Tools -> Internet Options ->Connections -> LAN Settings -> Its fine if any box is not checked. Or you can check the "Automatic Detection".
Last thing is If you have a Firewall or Antivirus Suite Please make sure that you are not blocking adapters and traffic/application. You can try to disable Windows Firewall and check whether it works as well.
Hope this will solve your issue. Please be kind enough to rate the answer with a comment (testimonial) if this helps you to overcome the issue. Feel free to contact us further. Thanks for contacting Fixya

Jun 05, 2010 | Siemens SpeedStream Modem (4100) (SS4100)

2 Answers

My Motorola Sb5101 modem will not let me access the internet, the send light constantly flashes and i can't attain any internet connection.

If you have the following lights :
Power light - on
Receive light - flashing
Send light - flashing
Online light - off
PC/Activity - on
Standby - off
Then your Network Access is OFF - modem is successfuly registered but Network Access Control is disabled via DOCSIS configuration file.

Call your internet service provider....

Nov 06, 2009 | Arris SURFboard SB5101 Cable Modem

1 Answer

The internet light is off all others green on the 5100 modem. Also, very slow internet and hard to go to various webpages. Will this correct itself over time or is there a quick fix?

You can try resetting the modem to factory condition.
Turn off the modem from power
Disconnect the modem from the computer
Turn on the modem
Press the reset button using a pointed object, (a toothpick or a pencil)
Wait for all the lights to flash green then release the button
Reboot your computer
Connect the modem to your computer

Everything should work fine.

If the problem persists contact the service provider.

Thank you for choosing Fixya

Oct 12, 2009 | Efficient Networks SpeedStream 5100 Modem

1 Answer

Motorola SB5100 Cable Modem Power Lght Flashes

Call your Internet Service Provider.
They can remotely "connect" to the cable-modem, and diagnose it.

Jul 16, 2009 | Arris SB5100 SURFboard DOCSIS 2.0 Cable...

1 Answer


You will have to be a bit more clear on which lights on which model of modem is flashing rapidly.
Usually, as long as the internet works, the flashing lights are there to show that the modem is functioning properly and is currently sending packets, transmitting data, etc.

Jun 19, 2009 | Actiontec (GS503AD3-01) Modem

1 Answer

Internet lights flashes then stops then flashes

its ok if the internet light on your modem is flashing. as long as its not off.

Aug 28, 2008 | Westell Wirespeed LiteLine 6100...

2 Answers

Arris cable modem

try shutting of your computer then shutting off the modem, the modems have batteries you might have to remove them theres usally a panel on the bottom, in the back you should have a wire for comcast cable and an ethernet chord telephone too if you have everything. also your modem could be broken, i had the same problem

Jun 06, 2008 | Arris Touchstone 450a (CM450) Modem

Not finding what you are looking for?

451 people viewed this question

Ask a Question

Usually answered in minutes!

Top RCA Modems Experts

Mike McWhinney

Level 3 Expert

537 Answers

Starnley Johnwells
Starnley Johnwells

Level 3 Expert

1029 Answers


Level 3 Expert

56631 Answers

Are you a RCA Modem Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides