U400 + iPhone 15: UWB works for some time only

I’m trying to get a U400 to work with my iPhone. NFC is always fine, but UWB is disappointing so far.
I have reset the lock around 10 times now, and 3 times UWB worked. But only for an hour or so.
Then, the UWB light doesn’t come on when the iPhone is close.
How can I debug this? Should I restart both devices? Once, that seemed to help. Should I switch Bluetooth off and on again on the iPhone, to trigger detection of the lock? That doesn’t seem to help.
Should I do something in the Aqara app or in the Apple Home app? So far, I think UWB only works via Apple Home, correct? And the Aqara app and Apple Home / Matter can NOT be coupled, entering the Matter pairing code will only result in a “not supported” error message at the end of the process, is that correct?
I have an Apple HomePod mini and no Aqara Hub.

1 Like

And I have also updated the firmware to V3110, but it didn’t improve this behavior.

1 Like

Hi @mh-mh - can you share some screenshots of the lock settings from both Apple Home and Aqara? Particularly interested in the approach direction as it relates to your door’s location.

What is your door’s location like? Is it elevated on any stairs? Anything unique about your door?

UWB settings can managed in either app, but Apple Home is going to be your main source.

This is not correct generally speaking, but because you have no Aqara Hub you cannot Matter pair to Aqara, but the Aqara pairing code might still work.

1 Like

Thanks for your reply!
The lock is mounted about 1m from the floor, so my phone is often slightly below; but there are no stairs involved.
I did not restrict approach direction.




But I also don’t fully understand how UWB works on the iPhone:

I thought it’s a feature of the Apple Wallet, so that it can work on the iPhone in the background. Configured through the Apple Home app.
Does it need Bluetooth to notice a “beacon” from the lock? If that’s the case, maybe switching Bluetooth off and on again might make the iPhone work with the lock’s UWB again?

But then, what’s the Aqara app’s role in UWB? Does the Aqara app have a separate UWB key (different from the one in the Apple Wallet), and does it also communicate with the lock when I’m walking towards the lock?

I think this is fairly typical height for a door lock. Can you share a picture of the door? That might help with understanding the approach path. It’s always worthwhile to troubleshoot systematically. You can try disabling Left and Right approach one at a time, testing each setting individually to see the impact.

You are correct in your understanding for UWB for Apple Home. UWB relies on the hardware of the device. Aqara’s app exposes the approach settings, which may be more useful for the Samsung wallet/Aliro use-cases. You wouldn’t be able to provision it on iPhone in the Aqara app alone.

This also happens to me but my door has alittle 6 inch rise so the lock sits higher than typical. If it doesn’t work when i bring my phone up a few inches from my pocket it unlocks.
I also get where it doesn’t work at all every so often but i imagine that is more a problem with my homepod mini than with the lock.