Cable Modem Troubleshooting: RCA DCM425

Light patterns, images, manuals and more helpful info for the RCA DCM425 cable modem –

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Manufacturer: RCA

Model: DCM425

Modem Light Indicators
Message Flashing – flashes to indicate unread email (only if ISP enables this feature)
Off – no email messages pending
Cable Activity Flashing – indicates data traffic; modem is in use
Off – indicates no current data traffic
Cable Link On – cable modem is connected to the network
Flashing – cable modem is attempting to connect to the network
Off – cable modem not connected to the network
PC Link On – PC is detected but no current activity
Flashing – activity between PC and modem
Off – no computer detected or modem is in standby
Internet On – If this and the Cable Link light are steady then the modem is connected
Flashing – modem is searching for a downstream signal
Off – power is not supplied to the modem or modem is in standby
Notes and Useful Information

Installation and User Manual, .pdf (1.05MB)
Manufacturer Website
Manufacturer Customer Service Page

62 thoughts on “Cable Modem Troubleshooting: RCA DCM425”

  1. Pingback: how to login to rca dcm425

  2. my internet keeps turning off after a while, the box say’s it has connection but my pc has no internet so i have to turn off and on the the box. this is incredibly annoying.

  3. Guys my job is based on the internet and whole lif i have the one light blinking problem and it say”no intenet acess help me”

  4. I just got this modem today because my old modem broke, but the issue i have is that when i try to connect my ethernet cable to the modem and plug it to the xbox for xbox live it says that it cant c onnect to the internet but the connection is all fine even thought when i plug the ethernet cable to my PC it works fine and i have internet and everything but it wont say iv’e connected to the internet on my xbox WTF is the problem and also a little side note it worked on my other modem everything worked fine on my other modem. i miss it :(

  5. Call your service provider first! Make double-damn sure it isn’t something on their end. Ask them to reset your connection from their end. That means they’ll need your account number/info. They pull up your account and reset your connection using their software. If the guy your talking to doesn’t know what you mean, then you’re talking to the wrong guy. If you’re using a hub or a switch, then you need a crossover cable between your modem and hub/switch. If you’re using a router (wireless or not), then you need a straight through cable between your router and modem. You always use a straight-through cable between your computer and modem/router/hub/switch, i.e. your computer always needs a straight-through cable. The modem comes with a straight through cable. Hubs & switches typically come with crossover cables. Routers usually come with straight through cables. The first time you connect, open your browser and configure your modem/router. Your browser should take you to the configuration page for your modem the first time you connect to it. If not, then you can try to pull up the page manually by entering in your web browser’s address bar, or you can try to “hard reset” your modem using the reset switch (tiny button) on the back. To do this unplug your modem for a few seconds, hold the reset switch down, and while holding the reset button down plug the modem back in. Continue holding the reset button down for 10sec. Now, open your browser again and it should take you to the configuration page. If your PC Link is flashing, then reboot your computer and/or “repair” your network connection (right-click tray icon). If your cable light is flashing, then you can try to soft reset the modem (press and release the reset button on the back); otherwise, you’ll have to hard reset as mentioned previously. Hubs & switches are passive. You can think of them like splitters. Routers, on the other hand, are not. Routers request an IP address from your modem, and assign dynamic (random) IP addresses to any devices connected to it, like your computer/PS3/Xbox/etc. You can connect as many devices as your router/hub/switch can handle. They will all be able to access the internet through your modem.

  6. I seem to be having the same problem as everyone else. At the most random (seemingly) times, the modem will stop providing internet, and will go into a mode where “PC Link” and “Internet” lights are continuously flashing. I have no clue what the problem is… I’ve rebooted several times, returned the modem, called Time Warner (good god those guys are the most worthless, pieces….), etc. to no avail. Has anyone found a solution.

  7. boa tarde caro produtores quero lhe pedir uma sugestao eu tenho cable modem guardado na minhas coisas eu fazer um teste na casa de um amigo pela cabo da net so que ele começa a piscar de um por um ate encontrar a conexao completa so que depois de meia hora ela para de explicar so pscar so uma luz queria saber se o modem ta com problema??? me mandem msg pro meu email – urgente

  8. When connected directly to the RCA modem, will get you the interface where you can access diagnostics and eventlog.

  9. Charles Erickson

    Is there a way or a website to see the signal strength of the signal for time warner cable so you can find out if you adjust a wire or something that you can have it at the best speed /strongest signal possible?

  10. Dear sir,
    i have rca router and i wanna to setup wirless network as i have likesys modem but when i plug cabel with pc all does not work pls advise what should i do to setup all

  11. I have RCA – model 425 with TW cable but I can’t connect on network, cable link led is flashing non stop, and all other are on all time. What now?

  12. Hey not COMCASTIC fellow,
    I can tell you a few things that might help —

    Signal Acquired at 711.000 MHz
    SNR: 39.5 dB
    Received Signal Strength: 0.4 dBmV
    Bit Error Rate: 0.000 %
    Modulation: 256 QAM
    This is the signal coming TO your modem. 711MHz is channel 11o. SNR is great. The problem is on your return, and you can help that by eliminating the split.

    Connection: Acquired
    Frequency: 29.6 MHz
    Power Level: 55.2 dBmV
    Channel ID: 11
    Modulation: 16 QAM

    The return is how you upload back to the cable co to ask for webpages, etc. The frequency ranges from 5 -40 MHz, with the 5-20 never being used because of noise. The power level is the amount of power your modem has to put back out to get to the headend at the requested level (usually zero db). Most modems shut off and reset at 60dBmV and try to re-acquire. You need to reduce that to 45-50 to keep a stable online connection. Each 2way splitter is -3.5db, so if you had the 2 way right where the cable comes in and the modem off one and the 3 way of the other, that would get you at least 3.5 bringing that 55.2 to 51.7. Some 3-way splitters are -5db so you might get it down to 49. If that doesn’t work, call it in.

    I just wonder where you got those numbers from an RCA modem.. Motorolas have the interface to do that, but I dont know about the RCA.

  13. hey, i’m trying to port forward and i can’t get the password. I enter my Default Gateway into the browser and it just asks for a pass. I have tried admin and other password that might work. None of them are good. Does anyone know how to change the password or what the password might be besides admin?

  14. javier mira, te cuento que hay programas en la red en lo que puedes buscar desde google para cambiar tu ip, hasta cambiar la mac de tu equipo que, asi podrias conectarte y bajar TRADICIONALMENTE l=prograsmas o cosas desde esos servidores, porque lo mejor y automatizado que puedes hacer es bajarte un programa que se llama jdownloader, es hecho en java y te da laposibilidad d q ingreses tu link y lo pone en tu lista y lo baja a la mayor velocidad posible y sin que te pida otra ip, eso si, si son muchos links, andate a dormir y a la noche siguiente los tendras todos listos,…. miiiiles de links los puedes hacer..

  15. hola q tal? paso a contar mi problema yo tengo el mismo modelo de modem pero quisiera hacer una consulta se puede cambiar la direccion de ip del modem? la verdad no tengo ni idea sobre esto lo que pasa es que quiero bajar musica de rapidshared o megaupload pero no puede siempre me aparece error y me aparece mi direccion de ip fija creo que es por esto que no puedo bajar mas por la ip hay alguna forma de cambiarlo??? desde ya gracias….

  16. solution!! ok guys , i was working in the office whit these modem and Broadband router cisco, ok, the first thing if the modem don’t not recognize you router and freeze the internet you need assign a mac direction in the router because the modem read ONLY one device o computer, and then turn of the modem and the router, plug first the mode,, wait 5 secinds plug the router, and then the modem read the device with MAC address and the router read the IP direction and then the router assign direction DHCP to the devices plugged s in there….
    ir you have some question my email es

  17. it IS NOT comcastic...

    Comcast, Indiana – This modem didn’t work from day one. When I first got it, the 1st two lights would come on and flash but it wouldn’t go any further. After 2 days on the phone with customer support a tech was able to get into my modem remotely and update a boot file or something that he said was bad. After that, the modem would connect and I was finally able to get online as long as I didn’t have a splitter branching off to my TV. Then later on the same night I rebooted my computer for something unrelated and now my modem won’t stop re-connecting. Once it connects everything seems fine but the connection only lasts for a minute or two and then it resets. I really wish I had one of the older Motorola modems they were using last year :(

    I’m a little confused why I’m not able to get a signal at all when I hook my TV up though… here’s the wiring layout:

    |—————–[my tv]
    |———————————[2 way split]——–[modem]
    service in—–[3 way split]——-[other TV(s)]
    |—————–[other TV(s)]

    if I take out the 2-way and go directly to my modem I can get a signal (but the modem still drops & reconnects almost like clockwork).
    Here’s the stats from my diag page:

    Signal Acquired at 711.000 MHz
    SNR: 39.5 dB
    Received Signal Strength: 0.4 dBmV
    Bit Error Rate: 0.000 %
    Modulation: 256 QAM

    Connection: Acquired
    Frequency: 29.6 MHz
    Power Level: 55.2 dBmV
    Channel ID: 11
    Modulation: 16 QAM

    does that mean anything to any of you guys?

  18. ok guys im working may be 1 week in one store whit this fuqin modem, ok
    i search the principal things of this modem and my conclusion is
    the modem read just one computer, ok, if you conect the modem w/ a router The router by default dosent have mac address so you need put one mac addres, and conect you computer to this router, this computer NEED have the same mac of the router and you have conecion, ok and the coneccion stiil working know….
    let me tray another computer whit the SAME mac address…

  19. answer to # 12

    switch off computer, router and cable modem

    plug modem into router WAN, plug computer into one of the router ports

    power up modem, wait a minute

    power up router, wait a minute

    power up computer


  20. I’m about ready to throw my phone against the wall!!! Today I’ve spent over 1 hr talking and going through the stupid prompts to speak to someone. My RCA DCM425 will not stop rebooting. I am now on my second RCA modem and had the same problem with the one prior to the RCA series im using. The tech came out the same day and sure enough, it was working when he got here. Now it’s back to the same. Anyone interested in learning how to start an internet business that isn’t run by a greedy corp? Let me know!

  21. TWC-NY .. for the past week, my wifi and even wired ethernet connection has been dropping and reconnecting. I finally got sick of it and decided it may be glitches in either mdeom or router or both and decided to reset it both by unplugging the pwr cord and re-pwring it.

    to my demise, now my connection is just completely dead, even thru wired ethernet. My modem doesnt seem to be communicating with my router at all and the “PC Link” light is just dead. I thought it may be have been my faulty router all along and it finally crap’d out after the pwr reboot so i pulled out my old ethernet router to test. wiht my old router, the PC Link light would blink only if i power on my router after my modem, but not vice versa.. but regardless of the PC Link being on and blinking, there is still no connection via ethernet cable.

    TWC CSR are very little help, if any at all… naturally they blame it on the router if the modem works fine thru direct ethernet connection from modem>comp. but how can TWO working routers suddenly STOP working? ethernet cables have been tested to work, so thats not the problem. Seems to be is issue w/ the modem now suddenly refusing to communicate thru routers. So ofcourse i ask about TWC’s wireless modem. Sales rep says it’s 5.95$ extra per/mo with EACH computer setup @ 50$ or so… and said Im not allowed to just rent and install myself, they MUST install on every computer for me. I asked how exactly are they going to install the wireless connection if one of my desktops isnt currently equuiped w wifi, or if they were going to use wifi cards on every PC/Laptop I have, she repeatedly told me, i dont have to worry about that, they’ll handle everything

    i even specifically asked if twc recently updated their modem software to no longer communicate with 3rd party routers and she answers “no, we don’t do that” .. .. but what is any of it worth?.. as anyone who’s familiar with CSRs, they are either clueless, misinformed, making up BS as they go, or flat out LIE to you.. hardly will u find a CSR that is actually helpful on their own, usually, we have to help them help us..

  22. same problem with me. modem would be working fine. then all of sudden, all the lights would go out. only internet light would be blinking. Then it would work again if i just restart the modem, then it would go off again. now i am removing the splitter and connect the modem directly to wall jack see how it goes. this is just so annoying.

  23. Im a new customer of TW using the modem(RCA DCM425 modem) they provided , the tech went to our house and install the modem all works well but after 1hour when tech is gone my internet loss connection , i call back the tech but says all is working fine b4 he left , so i troubleshoot myself , well this might help some folks out there ,
    I found the problem is on the 8db attenuator the tech connects to my modem he says its filter the signal goin to my modem but the problem is once the connection is loss it cant connect automatically unless you remove the attenuator and put it back again once the connection normalized.
    I never put back again the attenuator , works fine now.

  24. I also have the flashing internet light. It was working for 5 months and then 2 days ago nothing. And I am/was using a router with a built in switch to go wireless to g/f’s laptop and wored to a PS3, all with no problems. They say the signal is fine up to my building so must be something wrong inside the building. Odd thing is, I plugged cable into to tv, and it’s definitely getting tv data…

    I’m guessing modem’s busted, but they were also painting our fire escapes this week… what if they knocked something loose?

  25. router vs hub/switch

    There is a reason for your problems using a hub or switch. A router can do many things that a hub and switch can’t. A router can assign network i.p. address to the computers connected to it, whereas a hub and switch do not. This is why you can’t directly use a hub or switch as a router substitute. You can use a hub along with a router to provide access to more computers, but you have to have the router to assign the i.p. addresses.

  26. Dthin: I agree with HiddenPalm. It sounds like something is wrong outside of what you can fix inside you house (meaning something your ISP has to fix…).

    HiddenPalm: I’ve noticed the same thing — that I can’t use a hub or switch. I’ve used a U.S. Robotics wired router and a LinkSys wireless router and both work fine; however, when I try to use my 16-port switch (even on the other side of the router (meaning: computers -> switch -> router -> modem)), I still can’t get anything out of it. I’ll try out using my main computer as a gateway (I’ve got an nVidia networking card which can use dual connections), but that would slow down my connection more than I’d like, since it’s my gaming computer.

    This issue has been bugging me lately as well, seeming as we have seven devices that we’d like to connect (my roommate has a laptop and I have an Xbox 360, four desktops, and a laptop) which are all in different locations in our apartment. So, if anyone gets this resolved without having to use the extra gateway, please let us know. :)

  27. Hmmmm I got a lead on my problem above.

    My NetGear SW518 is a switch and my D Link is a hub and neither of them is a router and supposedly they can share an internet conection and that I would have to make one of the PCees and gateway to the internet. ANd that it needs to modem cards.


    Is this the case?

  28. So has any body got their network (more than one PC) working with this modem? And what was your solution?

    I can’t get it working. The router im using to network the PCees is a NetGear SW518. The one I tried before that was a D-Link DE-805TP.

    To switch Internet access between the pcees, I have to unplug the power of the RCA modem for two seconds and plug it back in and the computer connected to the router gets to have internet. Sometimes I have to do a “repair”. But only one works at a time.

    What is the answer to what is wrong with the RCA DCM425 modem when you have a basic network? or What am I missing?

    Does anyone know? What I read in this thread sounds like a foul corporate conspiracy. It makes me want to know what is really going on?

  29. i am having the flashing green LED on above the internet connection. tried everything…Did a hard boot of everything. Looked at the cable seemed fine,running wireless router getting signal. Also getting the DNS error thing when i go to look for a signal. Used the LAN cord direct still nothing…NY TWC if that means anything and in a house. Please, help banging my head with not being able to stream tunes and work online. Thank you

  30. Lost in translation

    Thanks again. I meant no snark, you answer was really good. Any snark is reserved for Time Warner and the Cable/telcom industry as a whole. The handle “lost in translation” just denotes a man lost in a world with strange values and customs.

    I was assuming that they had done their evil best to make life hard on people who wish to network, in an effort to sell more services. As for it being legal, a lot of the state and federal legislators rely on Telcom money to get reelected, so a lot of things are legal. (Some are even legal “retroactively”). That is likely the source of my jaundiced view of telcoms.

    Alas, I was wrong. In fact, that assumption got in the way of my experience – wisely recycling every thing in order before looking for a problem. Once I did that, everything worked fine.

    Finally, please do not get me wrong. Your answer was great and you write well. Keep it up

  31. Lost in Translation:

    I apologize for the jargon-filled answer I gave before. I got a little bit off topic, I know, but that was the best explanation I could give.

    Anyway, it turns out the internet LED was flashing constantly on our modem because someone had broken the door off our cable box (to our apartment building) and was stealing our connection, which is why we weren’t getting anything at all… Luckily, I got the cable guy to show me where everything was so I could reconnect my line if it ever happens again. :-P

    As for the wireless modem: my parents have Zoomtown (through Cincinnati Bell (local telephone service), which is separate from TWC), and they paid a certain amount to buy a modem/wireless router (it’s just a router with a built-in modem; this one was Westell brand). Perhaps TWC is just offering the service to keep up with their competition, since you can even get wireless in gas stations and fast food joints nowadays… It just sounds like they’re allowing you to, instead of just getting a modem from them and using only one connection or buying your own routers, get an all-in-one package to get them more money, etc. The device TWC will sell/lease you is most likely this one: RCA DCW615R.

    When I got my cable installed, however, they did say that I could just buy my own cable modem and that any would do (I went with their’s only so they would know their own stuff if I had to call tech. support…). I’m assuming it’ll be the same with the newer modem/wireless router.

    Also, I imagine they’re only advertising that “specially trained technicians will wireless connect your computers for a one-time installation charge” because many people, as you said, aren’t technically inclined, and would, therefore, have many problems or be clueless if they were just handed the modem and told “Here you go; have fun!” In addition, users would be able to get the technicians to set up security (password protection) on their wireless network. I know my aunt didn’t know how to do any of that when she got her wireless router, so I had to go set it up for her.

    As far as limiting you to one computer per household, I don’t even think that would even be legal. Seeming as you’re paying for the connection, you should be able to do whatever you want with it (assuming you’re not hacking or soliciting illegal goods or services, etc.). Furthermore, on my ISP’s web site, under “Help”, they have tutorials on how to set up home wired or wireless networks. I don’t think they’d do that if they’re trying to enforce the “one computer” rule…

    Hope it helps.

    P.S. — If you buy the modem or router, then it would be illegal, of course, for them to set up a password without you knowing or to configure it so you’re unable to use its features. It’s your property, they’re just supposed to set it up in case you don’t know how.

  32. Lost in translation

    Good explanation, but not sure it works for me. I still can connect to the internet directly through the RCA but not through the router. I do not have your technical expertise, but I do know how cable companies work and would not be surprised that Time-Warner is now using modems that will not allow routers. This suspicion of evil intent is at least partially supported by the fact that TW, in their constant effort to provide a better product for the customer, is now offering a wireless modem for an extra fee.
    I also find this rather ominous notation on their site:
    ” Our specially trained technicians will wirelessly connect your computers for a one-time installation charge, and Time Warner Cable will provide full support 24 hours a day, 7 days a week.”
    Could they have set up the modem so that they need to be paid to set it up correctly???

  33. Funny thing here is that they just hooked up our cable internet on Monday, it didn’t work right (and I was confused about the number of computers allowed being one as well…), so we called and they were sending a tech. today. Well, yesterday it worked, so we cancelled the tech…or so we thought. Tonight (Wednesday), the tech. showed up anyway. We told him everything was fine now and he left. Not 20 minutes later, the internet light starts blinking while I’m just checking my e-mail (I had just gotten home from work) and now I’m back to utilizing the neighbor’s wireless…

    Anyway, to help y’all understand the “one computer allowed” problem (I’m a comp. tech. myself, which is why I hate calling for techs in the first place), I’ll explain a little what they meant. For some reason, whoever wrote the software that’s on the modem (most likely a foreigner) wrote “number of computers” and thought that would be a significant English equivalent to “number of unique global IP addresses”. In reality, most private networks are this way; the only change, for the most part, is for big business or school networks.

    I qualify the IP address as “global” because everybody sees that address as you; no matter if you’re on your desktop as opposed to your laptop or even your Mac (God help you), any web site will still register that same IP address as the location for its host server to send information. It’s kind of like your street address. Your ISP owns a certain number of them, and you’re effectively renting it out from them. The cool thing is, IP addresses can be used to approximate real-world locations for where you are as well (down to a few square miles).

    Anyway, back on topic, once the information sent from some server somewhere reaches your modem, it has only one place to go: out. Some broadband modems have routers in them as well, but not this one. Anyway, if you’re connected straight to a computer or gaming console from the modem, then that’s where the information will go. Also note that, in this case, the machine connected directly shows its IP as the same as the global IP listed by your modem. Once again, this is because it’s the only place the modem can send the information it receives.

    What do I need to add more computers?
    You need a router, and I’ll explain why. The sole function and purpose of a router is to, well, route, or map out a path for, information which goes through it. For instance, you have three computers hooked up through a router (via wired or wireless connections); the three machines are now given a “local” IP address by the router so that it can systematically receive and send data to or from each machine. A local IP address just means that, even though your computer says that’s what your IP address is, it’s only recognizable *within* your own network. In fact, however, while all your computers are accessing the internet through your router, your router tags and sends all that information to the modem while the modem just passes it on; likewise, your modem receives all the information you request and just passes it straight through, leaving the router to do its job of “directing traffic” so to speak.

    Well, I hope I made that a bit more understandable…I know I can be long-winded. I hope someone now just tells us how to fix the stupid blinking internet light!

  34. it really if you add another machine to the network? that definitely parallels when I added my roomies they really enforce just 1 machine per account?!

    i have the fast blink and have to wait for a TWC tech to come out…

  35. Ugh.. last week the Internet light on the modem was flashing, and Time-Warner was going to send a Technician on Thursday. Lo-and-behold on Wednesday evening, it magically started working again, so I canceled the tech. Thursday night–you guessed it–we went back to the Internet light flashing again. Could this just be a dying modem? I’d hate to wait to get another appointment/wait around for the technician to come, only to have him swap out the modem.

  36. Same situation as Yoda, I think. Only it stopped working 2 weeks ago. All the lights are what they should be, and 1 PC connected straight to the DCM425 works (I have Time Warner and Earthlink not roadrunner). When machines are connected to Linksys router they stop working, and after replacing the cable modem at the TW walk-in center in waaay upper manhattan, I was ready to conceed the router may have gone bad. But I just brought it to work, and 2 laptops connected to it, and passed out to the internet JUST FINE. It works. I think I’m getting the run-around from Time Warner (gee, I think??) The router worked for 4 years w/o incident, it stops working suddenly, it does not work even after replacing the cable modem, but it works in midtown. WTF?
    Also, when I connect to the modem reports “number of computers allowed by company: 1” and “number of computers detected: 1” but I have the same service as 10 neighbors in the building what have multiple computers connecting all the time, and I pay the SAME thing. And they have Linksys routers, too!

  37. Yeah, same problem as you guys. My internet and pc link lights are constantly flashing and the internet will not work. The weird thing is is that it was working yesterday and the day before..perfectly. It also did this one other time where it worked and then the next day the lights started to flash again. What is going on? I hope someone answers these questions on this website..doesn’t look like it though.

  38. When the internet light keeps flashing ,it tells that the modem is not getting a downstream signal from your cable company.U can try to unscrew the co-ax and screw it back in and give a shot and also u can check the connections up to the filter if any …Better u wait for the tech to come …

  39. I am having the same problem right now… Internet light is flashing and nothing else. Time Warner cable wants to send a technician in FOUR days. I can;t last that long. Kyle – was your problem resoved?

  40. the internet light on the modem keeps flashing and i cant get on the internet…im not sure what the problem is… everything is connected properly… i just cant wrap my head around whats going on
    please help

  41. You could try going to the web interface, just open internet explorer and the usual default adress for these is either or . This should allow you to tweak the modem.

  42. Hi im trying to connect a console using my RCA modem model no.DCM425 im tring to set up a wireless network but the console cant seem to pick up the access point wat shoul i do

  43. Pingback: Cable Modems - Cable Modem Troubleshooting: RCA DCM425 - Simplehelp | Broad Help

  44. I’d like to know if there is a utility (software program) that will allow you to access this cable modem’s internals. See how the traffic is moving, etc. I’d like a “diagnostic” tool or something that will allow me to “administrate” the darn thing…

    any thoughts?

  45. I have this unit connected to my cable box and I would like to know, when the lights are flashing, are data being transmitted and if so?

    I have limited download specs, like 10gb per month, then I have to
    start paying. I would like to know if the cable company is padding my
    data stream with random bits, so I will use up my allotment sooner?

    Sorta like padding your cable bill, to milk more money out of you
    and charge you more for their cable modem service.



  47. Dunno why, but as of late, when I boot the modem up, the internet LED flashes and nothing happens afterwards. Normally, when booted, all of the lights flash, one by one.

  48. Pingback: Cable Modem Index - Troubleshooting info for 60+ cable modems - Simplehelp

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