Binding a Vallhorn motion sensor to a Sonoff ZbminiR2 in ZHA

Configuration Zigbee
1

Hi all, I'm trying to do something very basic and it is not working. I have a motion sensor (Ikea Vallhorn) and a relay that controls a light (sonoff zbminiR2). I have ZHA with a Sonoff usb dongle "E". I want the light to switch on when I am in the room.
So I wrote an automation. It works.

But now I want it to happen faster and independent from my HA instance.

So I tried to bind the switch directly to the sensor through the "manage device" GUI, selecting the binding tab on the Vallhorn, and selecting the sonoff switch as the bindable device. That seems to have worked, there was a green checkmark flash. I double checked the binding exists using ZHA toolkit, which tells me the correct clusters (endpoint 1 id 0x0006, occupancy and on/off) have been bound. The coordinator is also still bound but I want it like that. IIRC I can have the coordinator bound as well, or is that wrong?

Anyway, when I walk into the room, nothing happens. I can see the Vallhorn detects occupancy. But the switch does nothing.
I can read the zha_events from the log, and it seems that the Vallhorn sends a command immediately after it changes occupancy:

data:
  device_ieee: 5c:c7:c1:ff:fe:3e:c8:43
  device_id: 647a0359a04ad6da0fcf01821a47315a
  unique_id: 5c:c7:c1:ff:fe:3e:c8:43:1:0x0006
  endpoint_id: 1
  cluster_id: 6
  command: on_with_timed_off
  args:
    - 0
    - 200
    - 0
  params:
    on_off_control: 0
    on_time: 200
    off_wait_time: 0
origin: LOCAL
time_fired: "2026-06-16T22:51:34.856305+00:00"
context:
  id: 01KV9A4228K68R8WW7ZNYGZCXH
  parent_id: null
  user_id: null

Can anyone give me a clue what is going wrong? zha_toolkit.binds_get on the zbminiR2 gives null, but I think that is expected?

2

No answers, so I asked Claude instead. It first pointed me in the wrong direction (hence the edit on this post), but after some prompts it got me to the core of the problem. The miniR2 does not support on_with_timed_off, which is the command that the Vallhorn sends.
AFAICT, there is no way to adjust that command, so it seems that currently, this specific route of binding does not work. I did confirm in the process that binding to a button that sends plain "on" and "off" commands does work to switch the ZBMINIR2.

4

To be a bit more clear on what I wrote above: I found out that it is actually possible to bind the two devices. That works. But the problem is that the Vallhorn sends a command ("on_with_timed_off") when it detects motion, which the Sonoff does not respond to. So the two devices are bound but nothing happens so they might as well not be bound. If it would send regular "on" and "off", all would be fine, but that's not what the Vallhorn does, and I understand this is actually quite common for motion sensors. I wrote a feature request to Sonoff after my efforts (or I had Claude write it), to ask them to support on_with_timed_off in firmware. Unfortunately, they answered that they are not planning to do that at all.
The only routes I see are either doing a feature request to IKEA asking them to allow sending regular "on" and "off" commands from the motion sensor, or writing and flashing custom firmware yourself.