US/DS Light Blinking: What It Means & How To Fix It?

US/DS Light Blinking

Modern routers and modems contain US/DS lights, with these lights referring to the Upstream and Downstream connection.

US/DS light blinking occurs when your internet is either activated or is establishing a connection with the server.

However, a longer US/DS light blinking is a cause for concern as it means the router or modem cannot connect to the server and requires intervention.

There are various causes of this including an internet outage, cable fault, or a device fault. Some of these issues are within your control and some unfortunately are not.

In this article, we outline the key steps you should take to fix the US/DS light blinking to help you restore your internet as fast as possible.

Most of the steps we present are easy for you to take and not particularly complicated.

We also present some key frequently asked questions to help you navigate the world of routers, modems and US/DS light blinking.

What Is The Purpose Of US/DS Light?

US/DS is shorthand for upstream and downstream. A solid US/DS light shows the router to have a solid internet connection and is sending and receiving data.

When the US/DS light is blinking the router is attempting to connect to the internet server. If the blinking becomes fast with short intervals, this indicates the router is having difficulty connecting to the internet.

Why Does The US/DS Light Blink?

The cause of the US/DS light blinking could include internet outages, poor connections, firmware updates, cable faults, broken coaxial splitter, or a router hardware issue.

The first step should be to restart the device and see if that resolves the issue. If that is unsuccessful, you should refer to the router manual to read up on any specific information on guidance related to the router model.

The steps we outline below are recommended for all routers experiencing the US/DS light blinking issue.

Fixing US/DS Light Blinking

Flashing US/DS Light Fixes

1. Check for a regional internet outage

The internet connection issue may not be specific to your home. Sometimes, a whole community may experience an outage. This can be incredibly frustrating and unfortunately fixing the issue is not directly in your control.

If you suspect this is the case, check your ISP’s portal or mobile app. Typically, you will need to enter your postal address to find your locality, and the provider should post an update if there is an outage.

If there is planned maintenance, the provider should provide advanced warning, but this is not always the case.

You can also ask your neighbors to see if they are also having internet connection issues.

In these instances, our tip is to stay patient and wait for the internet provider to re-establish the connection.

If your phone’s 4G/5G network is still available, you can consider using a hotspot to access the internet while you wait for the internet to be restored.

2. Restart the Modem/Router Combo

Often the modem or router simply needs a reboot. You can do this in a couple of ways.

You can turn the device off at the mains by unplugging it and allowing it to rest for a few minutes. Then you can plug it back in and let the device establish a connection.

Both approaches are common ways of solving the US/DS light flashing issue.

3. Look out for defective or loose cables

Cable issues are a common cause of US/DS light blinking.

Sometimes if you keep your modem or router in a location that may get whacked, the cables can often come loose.

Router and modem cables can be sensitive, so even the slightest nudge out of place can cause an unstable internet connection and the US/DS lights to blink.

Faulty cables can also be a source of US/DS light flashing. Either they have aged, or been damaged through dampness or a water leak.

If you suspect the cause may be a cable issue, first check to see if all cables are securely fitted to the router.

If they are secure, check for any visible damage on the cables. For modems, the coaxial cables need to be fitted finger-tight.

While, if you use a coaxial splitter to access the internet and TV, check it for any damage.

If damage is found, replace the cables or splitter with new ones to resolve the issue, and fit them securely.

4. Use an Alternative Wall Outlet

Once you’ve checked your cables for any damage, another factor to consider is the wall outlet. Whenever an issue is encountered with a modem coaxial outlet, the US/DS lights will blink.

A damaged coaxial outlet will also prevent the device from connecting to the ISP and cause a blinking pattern.

Many houses and workplaces are built with multiple coaxial outlets. You should try another outlet and see if the issue is resolved.

5. Pay Internet Network Fees

Some internet service providers will disconnect your modem from the ISP if you have not paid your fees, which will cause the US/DS lights to blink when turned on.

This is often the case if no activity is detected over a long period, the provider may cut off the internet connection for the foreseeable.

To prevent this frustrating occurrence, you should find the internet service provider’s website and log in to your account.

Review the account payment section and pay off any outstanding payments or update the payment card.

6. Network Equipment Power Cycle

The modem acts as a connection point between the ISP and you. As a result, there is a frequent communication cycle which can lead to them being overworked and heated.

A power cycle is a good approach to preventing your device from overheating.

To do this, you can turn off the modem via the Power Button located at the rear of the device. Then, you can disconnect the modem from the power outlet and leave it the rest for five minutes.

Once rested, you can reconnect the device back to the electricity source and start up the modem.

7. Firmware Update

Often modems run on outdated firmware which can cause connectivity issues. When a firmware update is ongoing, it will cause the US/DS lights to blink.

Thankfully, firmware updates don’t take long to complete, so the US/DS light blinking will only persist for the duration of the update.

Don’t be tempted to reboot the device during the firmware update as it may cause damage to your devices.

Let the US/DS lights continue to blink until the update is finished. Firmware updates normally take 15 to 20 minutes to complete.

If you think your modem is running on an old firmware version, you can connect it via an ethernet cable to your laptop/PC. Once connected, log in to the modem portal and download the latest firmware from the advanced settings or utilities menu.

8. Reset to Default Factory Settings

A factory reset of the modem or router will return the device to the default settings.

To do this press the reboot button (often a pinhole button) and this will refresh the network settings and existing connections. The device will then automatically reload and provided there is no internet outage it should re-establish a solid internet connection.

9. Customer Support

Although it may not be your favorite task, contacting customer service can be an effective strategy if all other options were unsuccessful.

If you judge the modem or router to be faulty, you should contact the service provider and request a replacement device.

Frequently Asked Questions

What does US/DS refer to?

US/DS refers to upstream and downstream connections. This connection is visually represented through lights on your modem or router device.

What is the US/DS blinking duration?

When your modem is set up, the blinking can last for 5-10 minutes. A Firmware update can last up to 20 minutes.

If it blinks for longer than 20 minutes, this is a clear indication that there is an issue with the internet connection. You can then use some of the strategies outlined here to address the issue.

What is the typical time it takes for a modem to connect?

Generally, a modem takes up to 10 minutes to connect when set up.

What’s the difference between a modem and a router?

These two devices are commonly mistaken for one another, but they are different devices with different purposes.

A modem is a device that connects your home or workplace to the internet, while the router creates the network within the home or workplace.

The modem has a public IP address, while the router assigns a local IP address for your devices to connect to.

The modem uses the WAN network, while the router creates a LAN network.

The modem accesses the internet through a coax cable connection to the internet service provider (ISP).

The router connects to the modem, then to the various devices such as phones, computers, TVs, and printers to ensure the devices can access the internet.

Although both devices have historically been separate units, modern technological advances have led to the creation of modem router combos, to bring all functions into one device. Xfinity Wireless Gateways is a prime example.

Can a router work without a modem?

Although some modern routers are built as dual-function devices with a modem, this is not typical and the router relies on a modem to provide internet.

If you see the router as the middleman, it requires a modem to function. The internet connection brought into the home or workplace by a modem is then broken down into local networks by the router.

What is a gateway 2-in-1 device?

A gateway 2-in-1 device is a modern router/modem combo. These modern devices bring the functions of a modem and router into one device.

Many internet service providers offer gateways for rent or purchase as they are much easier to set up. These devices will also contain the US/DS lights for monitoring the internet connection.

Final words

In this article, we have presented various tips to help you resolve the US/DS flashing lights issue so that you can quickly restore a strong internet connection in your home.

When the US/DS lights blink you don’t need to panic, hopefully, you know this by now. US/DS lights are found on modems or routers and indicate whether you have a good internet connection.

There are many causes of the US/DS light blinking so you need to take time to work out your approach to solving the issue.

Sometimes, US/DS light blinking is harmless and relates to the modem or router being in setup mode or undergoing a firmware update.

If there are internet connection issues, generally, a reboot of the system, either through a factory reset or a power cycle reboot is the most effective way of removing the flashing lights.

Sometimes, the issue may be beyond your home modem and be a wider ISP issue so you will need to be patient.

Daniele Besana

Daniele Besana

Daniele is a freelancer consultant with 15 years of experience in network security, customer support, Linux and Salsa. He worked for Juniper Networks in Netherlands, providing support and consultancy on security projects across Europe and Middle-East.

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