Govee water sensors H5054

Hardware
1

Hi,

This topic has been surfaced multiple times in different ways, but one thing that doesn’t seem like people were able to figure out (yet): how to make the sensor heartbeat.

I have a dozen or so sensors, and they seem to have at least 3 different versions of firmware on them. One of them does send the heartbeat every 6 hours. Seems like that’s my first purchase of 3 sensors that came with the gateway way back when.

I tore down 2 of the sensors. One that does send heartbeat. One that does not. Someone else posted these images some time ago. Mine are exactly the same. Both versions have identical hardware. And yet. one sends heartbeat, one doesn’t.

I was thinking that firmware could potentially be extracted from the sensor with heartbeat and uplosded to the one without. But I can’t figure out what the IC is. Looks like it’s the 16-pin on the board underneath, and it has no markings. Only 8 pins are connected.

Any thought on what this chip might be? And how to do the re-flash.

Here’s a closeup:

h5054-ic
h5054-ic891×1034 222 KB

2

Hi Sergey,

You might be able to look in the fcc documentation for the device. Look at the device and see if you can fine the fccID to look up.

3

Nice idea! Found this device report:

FCC ID 2aqa6-h5054

But unfortunately the schematic diagram is not provided, even though it’s listed with PDF file size here: https://fccid.io/2AQA6-H5054

4

Some additional investigation into the pins:

1 - 3.3V (boost converter)
4 - Button (w/ pullup; clicking brings this pin to GND)
6 - ADC? (Battery voltage input)
9 - Digital out: LED
10 - Probe in (3.1V when OK, 1.2V when probes contact water)
16 - GND

Harassed ChatGPT for an hour trying to see what possible IC could that be, but nothing checked out when pulling up the datasheet. :frowning: