What you’ll see and hear from the Nest Guard

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Nest Guard doesn’t just sound an alarm. It speaks to you and lights up in different colors to help you easily understand what’s happening.

Guard’s lights, sounds, and spoken messages can let you know when something’s happening and guide you through certain steps like arming or disarming. We designed the audio and visual cues to be clear so you won’t be left wondering what’s going on.

Heads-Up alerts and security alarms

If Nest Secure detects a possible intruder while it’s armed, a spoken Heads-Up alert can let you know and give you a chance to disarm your system before the alarm sounds. Guard’s light ring will turn red and the alarm will sound after the Heads-Up countdown ends.

Heads Up vs. security alarm:

A Heads-Up is a spoken alert that will let you know what’s happening with Nest Secure. A Security Alarm is a loud siren that sounds when your system is armed and it detects a possible intruder.

Applies to: Nest Secure

You don’t want your security system to sound the alarm as soon as you open the door. So we designed Nest Secure to first give you a Heads-Up to let you know you need to disarm it. This can give you some time to come in and put down your things first.

Security Heads-Up alert:

If you haven’t disarmed Nest Secure with the Nest app before you enter your home, Guard will chime and the light ring will turn yellow. It will speak a friendly Heads-up message that asks you to enter your passcode. You can enter your passcode on Guard, hold your Nest Tag on Guard, or the app to disarm.

Guard’s light ring will act as a visual timer and show you how much disarming time you have left. When there’s only ten seconds left, Guard will say, “The alarm will sound in ten seconds.”

Security Alarm:

A Security Alarm is just that – an alarm that sounds when the system is armed and it senses that a door or window has been opened, or there’s motion inside your home. When Nest Guard sounds the alarm, the light ring turns red. It will also say “Security alert” and let you know what caused the alarm and the location.

For instance, it might say, “The front door was opened.” Everyone who shares access to your home with the Nest app will get a notification on their phone. Emergency services will not be automatically contacted in the event of an alarm. For more details, see the following article:

Whether or not you get a Heads-Up before a Security alarm depends on which security level it’s set to. The table below summarizes the basic conditions for everyday situations.

Learn more about Nest Secure modes:

What happened

Home and Guarding

Away and Guarding

Detect senses the door opened

Heads-Up alert

If not disarmed before time expires, Security Alarm sounds.

Heads-Up alert

If not disarmed before time expires, Security Alarm sounds.

Detect senses the window opened

Heads-Up alert

If not disarmed before time expires, Security Alarm sounds.

Alarm sounds

The alarm immediately sounds

Detect or Guard sense motion

Alarm won’t sound

Motion isn’t monitored in Home and Guarding mode.

Heads-Up alert motion

If not disarmed before time expires, Security Alarm sounds.

Detect’s button is pressed

Alarm won’t sound

Press to open a door or window with Quiet Open, or use a long press to check the Detect’s status.

Alarm sounds

The alarm immediately sounds.

Lights, chimes and spoken messages:

Other than sounding a Heads-Up or security alarm, Nest Guard was designed to quietly do its job behind the scenes and not distract you with chimes and spoken messages when you don’t want them.

What you see
What you hear
What it means

Green light ring countdown

Away and Guarding illuminated


After the countdown, the security system is armed. The alarm will sound if motion is detected, or doors or windows are opened.

Home and Guarding illuminated

The CHIME sounds

The alarm will sound if doors or windows are opened.

Off illuminated

The CHIME sounds

The alarm won’t sound.


Nothing The TONE sounds

A door or window has been opened while the alarm is set to Off


Info button Illuminated white


There are one or more things you might want to know.

Info button Illuminated yellow


There are one or more issues that may require attention.

Info button Illuminated red

EXAMPLE: “ NEST GUARD IS UNPLUGGED AND THE BACKUP BATTERY IS TOO LOW.” There are one or more issues that will prevent arming.


Yellow light ring countdown with number keys illuminated “PLEASE ENTER YOUR PASSCODE”

Heads-Up: the alarm will sound if you don’t disarm with your passcode or Tag before the countdown ends.


Pulsing blue light ring “USE YOUR NEST APP TO BEGIN SETUP.”

Initial setup is in process


Pulsing yellow light ring NOTHING

Nest Guard’s battery is extremely low and needs to be plugged in and charged before it can resume normal operation.


The alarm is sounding.

More about Nest Guard’s lights and buttons:

Keypad buttons

The keypad will light up when it’s time to enter your passcode or when you tap Nest Tag to disarm or arm. If the keypad isn’t lit up, you don’t need to do anything.

The Info button

If your Nest Guard needs to tell you something, the Info  button will be lit. Here’s how to hear what Nest Guard needs you to do:

– Make sure the security level is set to Home and Guarding   or Off . If it’s set to Away and Guarding , the next step will cause the alarm to sound.

– Press the Info  button on Nest Guard.

– If anything needs your attention, Nest Guard will chime and make a verbal announcement.

Light ring

Nest Guard has a light ring that can give you information about your security system or just help you find your way in the dark. In most cases, Nest Guard will also give you a spoken message when it’s displaying the lights listed below. The light ring is merely there to help guide you.

In general, here’s what each color means:

– Red: An alarm is sounding

– Yellow: You need to take action before the alarm sounds

– Blue: Setup is in progress. You may need to enter some information into the app.

And here’s a more detailed list of the things the light ring can tell you.

Light ring What it means and what you should do

Solid green light that gets progressively shorter

This is the countdown timer that prompts you to arm your system when you’re leaving home.

Solid yellow light that gets progressively shorter

This is the countdown timer that starts when your Nest Secure is armed and you come home.

Pulsing red

The security alarm is sounding, either because your system detected a potential intruder or because someone pressed the panic button. To stop the alarm, disarm your system.

Pulsing blue

In most cases, this means Nest Secure is ready to begin setup, starting with Nest Guard.

If you’re trying to subscribe to cellular backup, this light means Guard can’t find a cellular signal. If this is the case, Guard will automatically give you a spoken message about what to do next.

Spinning blue

There are a few things that a spinning blue light could mean.

  • Nest Guard is looking for Wi-Fi networks while you’re setting it up.
  • If you’re trying to subscribe to cellular backup, it’s looking for available cellular networks. After that, it will spin blue 3 times when it finds a network and activates the service.

In all cases, Nest Guard will automatically complete the process and give you a spoken message about about what to do next.