Fast Red Blink
Arlo Smart Doorbell
Severity: ModerateWhat Does This Error Mean?
Arlo doorbell fast red blink — typically several blinks per second — indicates a firmware update is in progress or an error condition.
During an update, do not remove the doorbell or interrupt power.
If the fast blink persists for more than 10 minutes with no progress, the update may have failed and the doorbell needs a reset.
Affected Models
- Arlo Video Doorbell (wireless)
- Arlo Pro 5 Wireless Doorbell
- Arlo Essential Wireless Doorbell
Common Causes
- Firmware update in progress (normal)
- Failed firmware update partway
- Internal hardware fault detected
- Battery very low and update couldn't complete
- Repeated WiFi reconnection attempts during update
- Recent factory reset re-applying firmware
How to Fix It
-
Wait 10 minutes.
If a firmware update is in progress, the fast red blink continues until the update completes.
Most Arlo updates take 5-10 minutes.
Do not interrupt by removing the doorbell or powering it off. -
Check the Arlo app.
Open Arlo app → device settings.
The app shows update progress if an update is running.
If progress is stuck for over 30 minutes or no update is shown, treat it as a failure. -
Verify battery level.
If the battery is low, the update cannot complete.
Remove the doorbell from its mount and plug in the charging cable.
Charge fully before retrying any update. -
Check WiFi signal strength.
Updates download over WiFi.
Weak signal at the doorbell location interrupts the download.
Stand next to the doorbell with your phone — if signal is below 2 bars, add a WiFi extender. -
Restart the doorbell.
If the fast blink will not stop after charging, hold the reset/sync button for 10 seconds.
The doorbell reboots.
The Arlo app rediscovers it and may reattempt the update. -
Factory reset as last resort.
If the doorbell is unresponsive after a reboot, factory reset.
Hold the reset button for 20-30 seconds until the LED blinks rapidly.
Re-add the doorbell in the Arlo app — fresh setup applies the latest firmware. -
Contact Arlo support if stuck.
If factory reset still leaves the doorbell stuck on fast red blink, the device has a hardware fault.
Within warranty (1 year), Arlo replaces it.
Out-of-warranty support varies — be ready to discuss replacement pricing.
Frequently Asked Questions
Will I lose footage during a firmware update?
The doorbell does not record motion events while updating — typically a 5-10 minute window where coverage is paused.
For most front doors that is a non-issue.
Schedule updates manually from the Arlo app outside high-traffic times if it matters.