Modem or router blinking red: what to check

A red light is a clue. The label beside it matters more than the color.

The answer in 2 lines. A red or flashing light does not have a universal meaning. It can indicate a connection problem, equipment trouble or another condition specific to your model. Check whether other devices can connect, inspect accessible connections and restart using your equipment's instructions. If the light persists, contact your internet provider using the contact information on your bill. Avoid a factory reset unless support explains why it is needed and how to restore your settings.

Start with these checks

Photograph the lights and note their labels. Identify whether the affected device is your modem, router, combined gateway or separate fiber terminal.
Check accessible power and network connections without opening equipment or disturbing fiber connectors. Look for a cable recently pulled loose by cleaning or moving furniture.
Try another device, then restart according to your equipment's instructions. If you have separate devices, ask support for the correct restart sequence.

Stop: danger

Smoke, sparks or a burning smell: stop troubleshooting. Keep away from damaged equipment and address the electrical hazard before trying to restore internet.
Wet equipment: do not handle a wet power adapter, outlet or device while it is energized.
Damaged outdoor lines: do not touch, move or attempt to reconnect them. Report the location to your provider.

Work out what has actually failed

Your Wi-Fi network can remain visible even when the connection to the internet is down. Conversely, a working internet connection does not guarantee that every wireless device can connect.

Only one device fails: check that device's connection before changing the whole network.
Every device fails: investigate the gateway, modem, incoming connection or a provider outage.
A wired device works: focus on the wireless connection rather than assuming the outside line has failed.

The City of San Bruno's cable-internet troubleshooting sheet illustrates basic modem and router checks. Use it to understand the process; your own equipment's instructions take priority.

What not to do

Pressing a recessed reset button just to restart: a factory reset can remove settings you need.
Repeatedly disconnecting equipment while it is starting up or receiving an update.
Opening a fiber terminal, looking into a disconnected fiber connector or trying to repair the fiber yourself.
Buying replacement equipment before checking compatibility, ownership and the provider's diagnosis.

Contact support with useful evidence

Use the support contact printed on your bill or available through an account you already trust. Explain when service stopped, which lights changed, whether every device is affected and what happened after restarting. Mention recent electrical outages or cable damage.

Ask whether there is an acknowledged outage, whether your account is active and whether support can check the connection remotely. Request a case reference and ask what happens next. Before accepting a visit or replacement, ask about possible charges and whether the equipment belongs to you or the provider.

Keep a short written record of interruptions and conversations. Ask for any repair estimate in writing, but treat it as an estimate rather than a guaranteed restoration time.

Credits and unresolved complaints in the US

Do not assume that a red light creates an automatic refund entitlement. Ask the provider to identify the outage-credit provision in your agreement and explain how to request a review. State consumer protections and contractual terms can affect your options.

For an unresolved equipment or service dispute, open the FCC Consumer Complaint Center, select internet service and describe the problem and requested resolution. The FCC's internet issue descriptions help you choose the relevant category, including equipment or billing.

For state-specific help, use USAGov's consumer protection directory: select your state or territory, then follow its complaint instructions. Neither route replaces contacting repair support.

Good to know

Save your equipment model and support contact somewhere you can access without home internet.
Keep ventilation openings clear and protect accessible cables from furniture and foot traffic.
Ask whether a restart will interrupt internet-based phone service, alarms or other connected equipment before proceeding.

Illustrative example: Jordan notices a red light after moving a desk. A network cable is loose, but reconnecting it does not restore service. Jordan photographs the indicator, avoids the reset button and contacts support using the bill. Support checks the incoming connection and explains the next repair step before Jordan buys anything.

A made-up story, for illustration.

Bobby

Sources, verification, confidence

Verified on November 5, 2026, for the United States. Confidence: high for complaint channels; medium for troubleshooting because indicator meanings, restart procedures and equipment responsibilities depend on the model and provider. Credits depend on applicable terms and state protections.