Updating U400 Firmware

[accounts5]

Just installed the U400 and want to update the firmware. I currently use the lock with HomeKit and an AppleTV as I don’t own a Matter or Aqara hub. The Apple Home app shows that there’s an update available, so when I click on it there’s a screen that shows Update Downloading with a spinning indicator. That’s where it sort of ends. The Home app will continue to sit there “downloading” forever - the longest I’ve waited was about 20 minutes. I’m not sure how big the firmware package is but I’ve got extremely fast internet and the lock works within the Home app as far as getting lock status and being able to lock/unlock it. Is there a better way to do the firmware update? The lock came with firmware v 3.1.0.0.

[Aqara-Harry]

Pro-Tip: How to Update Your Firmware Faster

Keeping your Smart Lock U400 up to date ensures you have the latest security patches and features. However, the speed of the update depends on which app you use.

Option 1: The Fast Way (Aqara Home App)

For the quickest results, we recommend updating via the Aqara Home app.

• Method: Bluetooth OTA.
• Time: Approximately 5–6 minutes.
• Requirement: You only need to be bound to the Aqara Home app via Bluetooth; an Aqara Hub is not required for this specific update method.

Option 2: The Set-and-Forget Way (Apple Home App)

Updating through Apple Home uses the Matter OTA protocol, which is significantly slower due to the way data is transferred over the Thread network.

• Method: Matter OTA.
• Time: Usually takes 30 minutes to over an hour.
• Recommendation: If you aren’t in a hurry, go to your Lock Settings in the Apple Home app and ensure “Software Update” is set to Automatic. Your lock will then update quietly overnight.

Summary: If you want the new version right now, use Aqara Home via Bluetooth. If you prefer convenience, let Apple Home handle it automatically while you sleep.

If you haven’t added U400 to the Aqara Home yet, the following link can teach you through how to bind U400 to Aqara Home via Bluetooth.

Guide: Setting Up Your Aqara Smart Lock U400

Dear Aqara Users, In this guide, we will walk you through the detailed steps to connect your Aqara U400 to the Apple Home app and the Aqara Home ecosystem, including how to bind it to an Aqara hub. We want this guide to be as helpful as possible. If you find any steps unclear or if you have questions that aren’t covered here, please leave a comment below. We are committed to assisting you and resolving any issues you may encounter. Your feedback is invaluable to us; it helps us understand real…

[accounts5]

Thanks for the reply. I performed all the steps outlined to bind the U400 to the Aqara app via Bluetooth but after I scan the magicpair QR code (not the matter code) and I press set, I hear the voice prompt about “to add a new user press 1…” and the app shows “Connecting…” then it fails. I pulled the battery to restart the lock and the same thing. I restarted my phone and it still failed. The lock is working in the Home app so I guess I’ll turn on auto update and hope for the best.

Also since resetting the lock was an option during BT binding I’m afraid to reset the lock at this point because I have it working in the Home app and I have programmed my family’s fingerprints into the lock. All of the setup and troubleshooting took me a couple of hours yesterday and was much more confusing than any other smart lock I’ve tried in the past. I manage many rentals and have smart locks on all of them so it’s not a foreign concept to me. But there’s so little in the way of information about this lock that I hope Aqara spends some time in developing more informative instructions and troubleshooting guides and videos that are immediately available to installers as opposed to combing through these forums. Sadly, it feels like early adopters such as myself are beta testers that had to buy the product first.