Diagnosing Internet Connection Problems Using the Modem/Router Lights

I've been surfing the internet for over 11 years now and I must admit that a slight slow down or any internet connection issue makes me irritated especially if I'm doing something important. Internet connection problems can be caused by a lot of things. The PC, the signal itself, the cables, or sometimes, it's just us missing something simple as plugging in the modem. Another annoying part of it is to diagnose what the actual cause is. But sometimes, it's as easy as looking at your modem and checking which among the lights are on and which are not. Modems vary from dial ups, to cable modems, to DSL modems, etc and they differ in how they show you the status of the connection. LED (Light emitting diodes) are the tiny lights on your modem showing you what is working and what isn't and it differs from modem to modem how it is shown and what lights you can see. Let me give you some tips on how to do a general diagnosis on internet connection problems just by looking at your modem to at least minimize or narrow down your search for the answer.

In almost all types/brands of modem, there is a Power Light that will tell you that the modem is on. In very few cases, internet connection problems are caused by as simple as an unplugged modem. It is sometimes due to the location of the plug or the modem itself that we can hardly see them. That's probably the most obvious mistake so just plug your modem in and turn it on. If you can't turn it on, plug in another device and if it works, there's probably something wrong with your modem. It won't hurt to contact your internet provider or the manufacturer of the modem.

For Cable and DSL modems/routers, they are usually connected to your LAN (Local Area Network)/Ethernet card. An LED showing the status of the connection of your modem to your LAN card is mostly likely on your modem. If it is on (and usually green), the connection is fine. It blinks from time to time (may not blink on some modems/routers) showing that data is being transferred between the modem/router and the LAN card. If it's off, the internet signal can't pass through to your PC. Check the cable that runs from the modem and the LAN card (The socket can usually be found at the back of your PC). Check your LAN card as well if it is enabled in your system and if it's working.

Another important LED indicator would be the DSL/Cable light (the name may differ from modem to modem so please refer to your modem/router's manual to identify which one is for the signal. For DSL modems, it would usually say DSL). It indicates whether the internet signal coming from the source/internet provider can't reach your modem. If it's off, it's usually either there is no internet connection at all (call your internet provider to check if there is an outage in your area) or it could be that the cables are lose or plugged incorrectly. Check your cables and see if they are firmly plugged in the right socket.

On some Cable/DSL modems, you have what we call the Internet light (it may be called by other names depending on the brand of the modem. Please refer to your manual). This indicates if your internet account is active and logged in. It's sometimes call as the Authentication light. If it's off or blinking, it doesn't necessarily mean that you don't have internet connection. You just can't log in to your internet account since there may be an outage in the authentication process of your internet provider or your account is inactive. It usually starts blinking when you turn the modem on and continues on for about an average of 30 seconds. It's trying to log in while it's blinking. When it stops blinking and the light is steady, that means your internet account is logged in and there is a very high chance that your internet is already working. If it is off or it keeps on blinking for more than 5 minutes, call your internet provider.

If you don't see an Internet light on your Cable/DSL modem/router, and you log in to the internet manually (by opening a program and literally typing in your username and password and clicking on connect), your modem/router doesn't log you in automatically. We call that PPPoE (point to point protocol over Ethernet). If your modem/router has a built-in pppoe, it logs in to the internet automatically for you.

For Dial-Up modems, the lights usually consist of Power, Send, and Receive. If you get a dial tone and when you try to connect to the internet, and the send/receive lights aren't blinking (it blinks if the modem sends or receives signals), it could be that your dial-up connection is having a problem or someone is calling you on the phone line you used to dial in. In most cases, especially if you don't have call waiting, if someone calls you on the phone, it will interrupt your internet connection and you won't be able to browse at all.

There you have it. Those are some simple tips on how to check your modem lights to initially diagnose the cause of your internet connection problems. Just take it step by step and rule out possible causes one by one. Again, remember that the lights differ from modem to modem and the names of the lights may differ even if their function is the same. If all else fails and you did everything you could, call your internet provider's tech support for assistance.