What Do the Lights on Your Modem/Router Mean?
Our experts will help you read your modem lights like a pro and fix your modem/router woes.
Whether you use a separate modem and router or a modem/router combo, you’ve got a lot of flashing and solid green lights on your internet devices. We’ll help you identify each light and troubleshoot common problems so your devices can have a strong internet connection.
Below are some of the most common lights you’ll run into on your modem, router, or combined modem/router device. We listed the lights in the general order that you might find them arranged on your device.
If you can’t identify your lights because they aren’t labeled and don’t match our illustrations, we have some suggestions a little further down.
The power light indicates that your modem, router, or modem/router has a reliable power source. Although it may flash or turn yellow when your device is downloading and installing routine upgrades, this light should normally stay solid green.
What does a red or black power light mean?
If your power light is red or not on, your device doesn’t have enough power to run. Ensure you’ve securely plugged your power cord into your device and wall outlet. If you’re still having troubles, the outlet you’re using may be faulty; try plugging your device into another outlet.
Modems and modem/routers have a downstream indicator, which is sometimes labeled “DS.” Some devices also combine the downstream and upstream indicators into one light. Either way, the downstream indicator shows that you’ve got a connection with your local internet provider.
After your modem power light turns green, your downstream indicator will flash green until your modem detects a signal from your internet provider. Then it will turn solid green.
Why won’t my downstream indicator stop blinking?
If your downstream indicator keeps blinking, it’s because your modem can’t detect any signal from your internet provider. Check to make sure you’ve connected your modem to the internet outlet in your wall—your internet provider may have either a DSL or coaxial cable connection.
If your cables are secure, your local internet connection may be down, or there may be problems with your internet service account. Contact your internet provider for more information.
Contact your internet provider’s customer service:
Modems and modem/routers also have an upstream indicator, sometimes labeled “US.” This light shows that your modem has a solid connection so it can upload—or send—information to your internet provider.
After your downstream indicator turns solid, your upstream indicator will flash while establishing your uploading connection to your internet provider. Then your upstream indicator will turn solid green.
Why won’t my upstream indicator stop blinking?
If your upstream indicator keeps blinking, it’s because your modem isn’t getting a response from your internet provider and can’t establish a strong connection. Contact your internet provider for more information.
Online indicator/internet light
The modem light labeled “online” or “internet” represents your solid, ongoing connection to the internet.
After your downstream and upstream indicators turn solid green, your internet light will flash as it establishes your IP (internet protocol) address with your internet provider. Then it will turn solid.
Sometimes, your modem may lose the internet signal. It will then have to reestablish a connection, which will start back with a flashing downstream indicator.
Why is my modem internet light off or red?
An unlit or red internet light may indicate trouble verifying your internet service login and password, so your local internet connection is probably down. But if you’re installing your modem for the first time, you may need to contact your internet provider for your login information.
Modems have only one Ethernet port in the back, and the link light lets you know you’ve correctly connected a device to this port.
Most people connect their modem to a router through the modem’s single port, but you can also connect a single computer to it.
Modem/routers don’t have link lights because they have a router built-in. Instead, you’ll see Ethernet or LAN lights.
Should my link light be flashing?
Link lights constantly blink—the flashing is a signal that your link port is active and sending information to your computer or router. If your link light is solid green, it’s connected but not currently transferring data.
Some routers have WAN lights that let you know that you’ve correctly connected your modem and router through the link port on the modem and the WAN port on the router.
Your WAN light should be solid or flashing green. If it’s unlit, check to make sure your router’s WAN port is correctly connected to your modem by an Ethernet cable.
The Ethernet or LAN light may look like the link light above, but it has a slightly different purpose. Link lights are for modems, which have only one Ethernet port. LAN lights are for routers, which have multiple Ethernet ports so you can connect more than one device to the internet.
Your LAN lights might be labeled “Ethernet,” “LAN,” or simply numbered. These lights will stay off unless you connect a device to your router’s Ethernet ports. Then, the light that matches up with the port you used will turn a steady or flashing green.
Your router or modem/router has a Wi-Fi light, which may be labeled “Wi-Fi,” “Wireless,” or “WLAN.” You might even have two lights labeled “2.4G” and “5G”—these represent the two separate frequencies in your dual-band Wi-Fi (2.4 GHz and 5 GHz).
Whatever your Wi-Fi light is labeled, a green light indicates that your router is broadcasting a Wi-Fi signal throughout your home so you can wirelessly connect your devices. A flickering light is fine, and it means your network is active.
Why is the Wi-Fi light red on my router?
If your Wi-Fi light is yellow or red, this indicates your router is vulnerable to security threats. To keep your online data safe, make sure you set a password on your Wi-Fi, and consider using a VPN for extra protection.
Why is my router’s Wi-Fi light black?
If your Wi-Fi light is unlit, your Wi-Fi is off. Try pressing the Wi-Fi On/Off button on the back of your router. If that doesn’t turn your Wi-Fi light green, then unplug your router and wait 15 to 20 minutes for it to turn off completely. Then plug it back in and give it time to reconnect before rechecking the light.
Your router or modem/router may have a WPS (Wi-Fi Protected Setup) light and button, which is a handy way to quickly connect devices to your Wi-Fi without using a password.
To use the WPS button, first open up the Network menu of your internet-ready device. If a WPS option is available, select that. Then push the WPS button on your router or modem/router until the light turns on. It may take up to a few minutes to establish a connection.
Your WPS light may turn yellow or blink while you’re trying to connect a new device. When you’re not trying to connect a device, the WPS will stay unlit.
How do you read a modem light?
Though many modem/routers label their lights with clear sans serif descriptions, some expect you to decipher the lights like you’re an expert in hieroglyphs. Yikes.
If your device doesn’t have labels on the front, first check the back. You may have to pull out a magnifying glass—there’s usually tiny print explaining what each light represents.
Failing that, try a search for your device’s model number. There’s a good chance you’ll find a manual online (we don’t expect you to keep that jumble of papers lying around your house). Your device’s manual will give you a detailed guide on each of your lights and their meanings.
Should all the lights on my modem be green?
The power light, downstream indicator, upstream indicator, online indicator, and link light on your modem should all be green.
If your power light is yellow, it may be upgrading, so leave the modem on and give it a little time to do its thing.
And if the internet light is red, it’s probably because your local internet service is down. You can try restarting your modem, but it probably won’t fix anything. You’ll have to wait for your internet provider to fix the problem on its end.
Should all lights on my modem be solid?
The downstream, upstream, and online indicator lights will flash while connecting but should stay solid once your signal is locked in. The link light will continue to flash, showing that the link is actively sending data.
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Final take: Green lights are terrific, and flashing lights are just fine.
When you take a quick gander at your modem/router, check that all the lights in use are green. It’s normal for your link light, WAN light, and Ethernet lights to blink—this shows that they’re all working hard.
Here’s hoping things are green across the board for you and your modem/router.