Error %d, %s accessing 0x%02X: Check your I2C address ((None, None, 26))

[Sagi-tab]

Hi Misiu!

Thanks for your hard work on this integration 🙏🏼
I started getting the above alerts yesterday after a restart I performed. No other changes I can thing of.

Some necessary info:

Installation method Home Assistant OS
Core 2025.7.4
Supervisor 2025.07.3
Operating System 16.0
Frontend 20250702.3

Using Argon ONE M.2 for Raspberry Pi 4

I2C installation method - The official way (and I verified it using the add-on, just in case)
Integration installed through HACS

Seems like this is stemming from: Source: custom_components/argon40/init.py:73 -
bus.write_byte(I2C_ADDRESS, 10)

This error originated from a custom integration.

Logger: custom_components.argon40
Source: custom_components/argon40/__init__.py:73
integration: argon40 (documentation, issues)
First occurred: 15:36:12 (1 occurrence)
Last logged: 15:36:12

Bad logger message: Error %d, %s accessing 0x%02X: Check your I2C address ((None, None, 26))

Please let me know if I can assist with collecting more info or if any further information is needed to debug this.
Thanks!

[Misiu]

@Sagi-tab, if I understand correctly, the integration worked and stopped working.
Did you update the HAOS? I found an issue with HAOS 16.0 - home-assistant/operating-system#4189 it is related to 1-Wire, but it is GPIO-based, so maybe a related issue.
Please confirm which version of HAOS you are using. Thank you.

[Misiu]

I just noticed you are using HAOS 16. Can you roll back to 15.2? Just to confirm everything works.

[Sagi-tab]

Rolled back to 15.2, but the issue persists unfortunately.
I even tried removing the integration and re-installing it. The same error message is still showing up when the system starts.
Any other logs you'll be interested with @Misiu ?

[Misiu]

Try enabling I2C again using configurator. Maybe something roller back the changes

[Sagi-tab]

Also re-confirmed:

/dev/i2c-1 /dev/i2c-0 /dev/i2c-1 /dev/i2c-10 /dev/i2c-22 Found i2c access! Nothing to do! You can remove this add-on. Live

The strange thing is that it happened only today, after a restart. Nothing really changed and all of a sudden I started getting Setup failed for custom integration 'argon40': Integration failed to initialize.

[Misiu]

Could you try to test a fresh HAOS 16 on a spare SD card?
I'm waiting for a new PI to try to recreate the issue on HAOS 15.2 and 16.

[Sagi-tab]

Unfortunately I don't have any other available rbp to test it on. Any chance this has something to do with the fact I'm running on rbp with nvme instead of an SD?

…

On Tue, Aug 5, 2025, 10:09 Tomasz ***@***.***> wrote: *Misiu* left a comment (Misiu/argon40#92) <#92 (comment)> Could you try to test a fresh HAOS 16 on a spare SD card? I'm waiting for a new PI to try to recreate the issue on HAOS 15.2 and 16. — Reply to this email directly, view it on GitHub <#92 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AVSVMGWWOI6O7RYCKXOOJ4D3MBKB7AVCNFSM6AAAAACDB6LDQCVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTCNJTG43TMOJQHE> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[nimnal]

Good day! Tell me, do I understand correctly that at the moment this automation does not work on the current version?
I have it installed HAOS:
Type: Home Assistant OS
Core: 2025.8.3
Supervisor: 2025.08.3
Operating System: 16.0
User interface: 20250811.1
...and it does not start and does not work in any form, although I2C successfully starts and works on the host.
I tried installing the integration manually, as well as adding it via HACS.
Best regards!

[Misiu]

@nimnal I'm waiting for a new Raspberry PI 5 to test things out. I destroyed my last unit due to bad wiring.

How do you verify the I2C starts and works?
If I remember correctly, you need to start the I2C Configurator twice - see the FAQ in https://community.home-assistant.io/t/add-on-hassos-i2c-configurator/264167.
You need to do hard reboot, not a normal one. Maybe that will help

[Sagi-tab]

Funny thing - I don't know if it was the latest updates that were pushed or the power outage I had the other day, but the integration started working again all of a sudden.
Could you try it as well @nimnal ? Try shutting down the RBP completely, disconnect it from the power supply and then connect it and turn it back on.