A red light on your modem doesn’t always indicate a problem. Some manufacturers use red to show that a device is on, but it’s generally not a color you want to see on your modem.

How to Fix a Red Light on a Modem

To address the red light on your modem, follow these troubleshooting steps. If the light changes to green or amber after trying a step, check if your internet is working. If it is, you can stop the troubleshooting process.

Here’s how to fix the red light on a modem:

1. Restart your router. Unplug your modem/router from power, wait at least 30 seconds, then plug it back in. Wait while the lights cycle, and see if the red light goes away.

2. Check for service outages. The modem’s red light may indicate that your internet service provider (ISP) is experiencing difficulties delivering internet to your home. If so, you’ll need to wait for them to resolve the issue.

   To confirm, contact your ISP. Their website may feature an outage map you can check. Alternatively, conduct an online search for your ISP’s name to see if any news outlets have reported an outage.

   If you can’t access the internet through your modem, use your phone’s mobile data connection to go online via your phone carrier.

3. Check the connections. If you have a cable modem, check the coaxial connections at the modem and the wall. Make sure they’re tight and not corroded.

   If you have DSL, check the phone line connections at the modem and the wall, and make sure the wires aren’t frayed. If you find a loose connection, tighten it.

   You may also need to restart your router after fixing it.

4. Try a different outlet. If your house has multiple phone or cable outlets, connect to a different one. If none work, there may be a problem with the wiring in your walls or the connection where the cable or phone line enters your house.

5. Try a different cable. If you have another coaxial cable or phone cord, try swapping it out with the existing one.

6. Reset the modem. Use a paperclip to press and hold the reset button on the modem for up to 30 seconds. This will restore the modem’s default settings, which may resolve the red light issue if it’s software-related.

   Resetting the modem will remove any customizations you’ve made. Depending on your use, this might erase passwords, DNS settings, and firewall configurations.

7. Check your internet credentials. If your modem admin portal has a place to enter ISP login credentials, make sure they’re entered correctly. If it doesn’t, you’ll have to contact your ISP to ensure the modem is correctly provisioned.

8. Let the modem cool off. If it’s hot to the touch, the modem might be overheating, causing the red light and possibly also other problems. You can shut down the modem and unplug it from the wall for a bit to cool it down.

9. Contact the manufacturer of your modem. The red light may indicate an internal fault. If it does, the modem will require service or replacement. The manufacturer will be able to tell you if that’s the case.

10. Contact your ISP. If you’re still having trouble with the red light, contact your ISP. Not only can they confirm if there’s an internet outage, your ISP can also identify noise on your line and any other problems outside your control. If you rent your modem from the ISP, they can replace it.

Causes of the Red Light on the Modem

A red light on your modem typically means it can’t detect an internet signal and can’t connect. To fix this issue, you’ll need to go through several troubleshooting steps.

Every manufacturer places a slightly different set of indicator lights on their modems, and the colors of those lights can mean different things from one model to another. Most modem lights tend to be green, and a red light usually indicates a problem or fault.

When you see a red light on your modem, it typically indicates:

• No cable or DSL signal is detected on the line: Your internet may be out, or there may be a connection problem.
• Failed authentication with your ISP: The modem can connect to the internet, but your account isn’t recognized. Try entering your credentials again if your modem has that option, or contact your ISP.
• Modem failure: If the power button blinks red and the modem isn’t working, it may have suffered an internal fault. Contact the manufacturer if you own the modem or reach out to your ISP if you rent the device from them.