I have two lights near the front door at our house. Inside. I call it the “Foyer”.
Every night when I go to bed, I set a scene that lowers all of the lights in public spaces in the house to what I call “nightlight mode” (basically if you need to get up, go to the bathroom, kitchen, etc you should be able to do so without having to adjust the lights).
The foyer lights are in a pair in the Home.app and get set to 20% for nightlight mode.
Tonight I noticed that a few seconds after I set nightlight mode, it was no longer highlighted.
I swiped thought and saw that the foyer lights were at 100%. I set the scene again, they went to 20%. A few seconds later they went back to 100%.
Lather, rinse, repeat.
Finally I turned them off at the switch. That worked. But as soon as I turned them back on they went to 100%.
I tried adjusting them separately and one had no problem going to 20% but the other would get under 30% and then start flashing before going back to 100%.
I turned off all the automations in the Home.app to make sure nothing was triggering it. No difference.
Now, I’m stumped. The only thing I can think of was that there was some kind of recent update that said, basically “You can have your lights automatically adjust to conditions” and I think I enabled that. That may be what is doing it. I can’t figure out where to check to see if that is what is doing it or where to try turning it off. It’s also 2am and I’m wiped so maybe I’m missing something obvious.
So this morning that light is still stuck at 100% and I’m guessing it’s just faulty. I’ll probably replace it next time I see some Hue lights on sale. In the meantime I’ve decided to just not let it bother me.
Ah, a single fixture with one working and one not. In that case swapping them in the fixture sounds like a good test. Then you will know if the fixture is the issue or the particular bulb.
There are lots of posts online about resetting Hue lights. It looks like there are varying levels revolving around the Hue hub being the absolute controller for Hue bulbs.
Here are a few varying examples around during simply deleting to reset through to requesting a reset command via a dimmer or the bridge and the Hue API.
Since everything is connecting via the bridge and their are keys exchanged for control, I guess they are just broadcasting and so the reset is quite basic.
I guess one more thing to check (Settings > Software Update) is that if you don’t have automatic software updates enabled, that you also don’t have any firmware updates pending for bulbs in your Hue app.
It could be the HomeKit Adaptive Lighting feature that would have been available with an update to your Hue lighting?
I did receive a similar alert but chose to ignore it, I then wanted to find out more but wasn’t sure what to look for. It looks like you can add the adaptive lighting to a scene or a bulb, the article above explains what to look for.
If it’s not that then in the Hue app you can check for routines from other apps in the Routines tab. This is where a third party app can add something to the hub, I have one that I use as an alarm that flashes a set of lights.
Have a look in Shortcuts in the Automation tab to see if you have anything that is set up in the ‘My Home’ section, I have a few routines that switch on and off the outside lights, and the lounge lights in the afternoon etc.
Good luck, I have had to do this for my parents a few times when their automations fail, I’ve slowly eliminated all the third party apps and managed to get most things done in Shortcuts.
Having one flaky bulb among many is a classic sign of a problem with the network mesh connecting the bulb to the controller - a Zigbee mesh in case of Hue bulbs and hub.
Zigbee meshes are pretty good about rebuilding themselves, so I’d start with physically removing power from that bulb and the other Zigbee devices near it for a few minutes as a first step. Factory resetting the bulb and re-discovering it is the next step to try. While some smart bulbs can be reset with a pattern of turning the power on/off, Hue bulbs require a reset from the controller. Unfortunately, I’m using a SmartThings controller, so I don’t have first-hand advice on how to reset using the Hue hub. A web search turned up a lot of suggestions, though, including this very geeky one.
“The only way to win is not to play.” 