@syssi or anyone else… I am having an issue with a Smartmi Pure Humidifier where the metal connections are no longer recognizing the bottom tub and sensors. The top which has the power wire connected turns on and the fan runs but all the water indicator lights are showing full even though the tub has little or no water. I have tried various levels of water, no change. Also if you pull the top off of the tub and the metal connections separate, the top is supposed to turn off. It does not turn off. It stays on. So it seems the top thinks it is connected to the tub with a full tub of water no matter what. Everything else works such as controlling through the app and HA. But it is just the sensors and the metal connections. I have tried removing the device from the app, resetting the power. I do not know of a factory reset or way to reset the connections.
Would really love to salvage this thing as it is only a month old and I have opened a ticket with Gear Best. When it worked, it worked great.
Try to identify the type of the sensor. I can imagine an analog sensor. Two wires next to each other attached to the water container. A analog-digital converter measures the resistance in between. If the resistance is high the water tub is empty. If the resistance is low because of the contact to the water the tub is “full”. In this case I assume the contacts/wires are short closed may be somewhere at the top because you can detach the water tub and the device still indicates a full tub.
Standard component Xiaomi Air Purifier in Home Assistant with this humidifier does not work, I tried both available models in the component, but in no way: