All ESPHome devices are not connected anymore to wifi, their fallback hotspot is active

ESPHome
1

Hello everyone,

Today the power grid was disconnected again, this happen last week once too, does anyone know what could cause the disconnection of all my ESPHome devices (15 different kind ESP32, ESP8266).

Each device has it’s Fallback Hotspot active , I tried to login, selected the wifi , inserted the same password … but still nothing, it can’t connect.

Nothing changed in the past 6 months, since January or february I haven’t checked HomeAssistant and I haven’t updated it, I did this a few weeks ago, one update only, today after I noticed all ESP are disconnected I updated Home Assistant Core and Home Assistant operating sistem to the latest, the tablet dashboard works just fine, but all ESPHome devices are offline.

I haven updated ESPHome builder yet

ESPHome Device Builder

Installed version
2025.12.7

Latest version
2026.3.0

  • Installation methodHome Assistant OS
  • Core2026.3.3
  • Supervisor2026.03.2
  • Operating System17.1
  • Frontend20260312.0

I noticed that all devices in ESPHome Builder have the UPDATE button active (Update available: 2025.12.2 > 2025.12.7 or on other devices 2025.12.4 > 2025.12.7 )

It is very weird to me why all devices don’t work, the wifi password did not change, the wifi SSID did not change. The wall mounted tablet works just fine, connected to the same wifi. RaspberryPi is connected via LAN.

Can there be some incompatibility in the 2025.12.2 or 2025.12.4 firmware with the latest Home Assistant versions that could make them not connect to wifi?

PS. I do not live in that apartment, it’s rented, I will go tomorrow with a laptop to to try resolve the situation
PS2. I have an UPS ready to be installed, I just didn’t had time to make some longer cables to a bigger battery that could run the raspberryPi/router/switches for many hours.

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2

Have a look at your router. Did you assign fixed/reserved IP-addresses? Did you configure the IP-address via yaml? The ESPHome version does not have anything to do with your problem.

3

No, all the IP’s ware reserved using DHCP, the devices do not have static IP’s

The router has the same external IP, I connect to the dashboard from a remote location, all devices like TV, Tablets, Phones connect to the router with the same old password, even my phone connected to the same wifi using the password I set back in octomber 2025, it’s the first time I’m going again at that apartment since january 2026.

the code in the esp YAML looks like this :

wifi:
  networks:
  - ssid: !secret wifi_ssid
    password: !secret wifi_password
  - ssid: dlink-A6C5
    password: c..............9

  # Enable fallback hotspot (captive portal) in case wifi connection fails
  ap:
    ssid: "Esp32-Mos-X4-B Fallback Hotspot"
    password: "D...........j"

The secondary SSID is not available, I wrote the code like this thinking I might install a secondary router, in case the main one will have some issues. The ESP do see the main router SSID with FULL power, the secondary SSID is not yet available

4

I don’t think the configuration for two access points is a problem. I’m using the same for one of my devices and that is working as expected.
Did you change the wifi SSID or password after you deployed the esphome firmware to the devices?

5

Can you resolve their IP by their mDNS (local) name? Can you ping them by IP?

And then visit them directly by their IPs?

6

I have some esphome devices with firmware level 2025.10.2 and one with 2026.2.4 and i have migrated my home assistant from 2025.10 up to 2026…3.3 release by release yesterday and i did not see any problems with the esphome devices.
If the fallback AP is active it means that the wifi connection could not be established.I would focus on the wifi router or other network components.

7

@juergenjw The devices worked flawlesly since octomber - january when I installed them, no code change since than.
SSID of the main router is unchanged, password is unchanged, the same in the last few months.

If the fallback AP is active it means that the wifi connection could not be established.I would focus on the wifi router or other network components.

That’s what I suspect too, but it’s weird that absolutely all ESP devices are offline, and all other devices like tv, phones still work with the same wifi.

@busman I haven’t tried pinging them but I did tried to access one device by mDNS directly from ESPHome builder, it did not work. 100% the devices are not connected to the wifi, that’s the reason I could see all Fallback Hotspots active, I haven’t counted but for sure there ware more than 10 Fallback hotspots active. I only tried to connect to one of them from my mobile, I than selected the SSID from that list , inserted the same password I used on my phone to connect to that wifi and I only seen an green highlighted message , something Like Connecting to the network … but no confirmation message that in fact it connected successfuly.

I will check if both 2.4G and 5G SSIDs are available, as I did not checked today in my short visit to the apartment, but I wanted to hear as many ideas from you guys too , so tomorrow I will have a full list with things to try :slight_smile:

Thank you. I will let you know if I will fix it.

8

Since it’s an apartment, also check that one or more of the neighbours isn’t sharing the 2.4GHz channel with your router and causing interference.

9

If you have an Android phone you could try the Wifi analyzer app to find the networks in your area. I don’t know if a similar exists for an iPhone.

10

Apple do not allow that.

11

If all your ESPhome devices go to the fallback AP, then your network have issues.
Check your router and APs.

12

Maybe this solves your issues, is in the last esphome update.

13

It doesn’t solve the problem, but ap function at home is not necessary. I don’t have it in any of my esphome’s, i only enter ssid and password and that’s it (and static IP’s).

While ap mode is very usefull for, say, situations when you wanna sell modules (or give them to another one) or similar, it’s needless in home situation, it can only cause problems. Without ap an absence of wifi connection will reboot whole module after set time, with ap it goes into ap mode and problems are here.

But, i agree with Wally: it must be a network problem if all devices go down. First restart your router, then check all settings…

14

It was the router, Orange uses some crappy ZTE F6600R routers and I was so stupid I haven’t tried to restart it in the first place :blush:

My phone was working with the router, the TV was playing a movie from netflix … it seemed to me that the router is just fine, the wall tablet was connected to the homeassistant running on RaspberryPi … everything worked except all ESP’s

Today , after I purchased a new AP to install it in the attic as a secondary wifi, I said to myself: what if I should first try to restart the router ? I was amazed to see all the ESP connecting after the router rebooted … stupid me…but it was an easy fix