Sonoff ZBM5-1C-80/86 Configure fails in no-neutral end-device mode: no output cluster genOnOff

What happened?

A SONOFF ZBM5-1C-80/86 installed without a neutral wire fails its Zigbee2MQTT configuration immediately after pairing.

The device interview completes successfully and Zigbee2MQTT correctly identifies it as a ZBM5-1C-80/86. The subsequent configure operation repeatedly fails with:

Failed to configure '0x4c97a1fffecfbbda', attempt 7
Error: Device 0x4c97a1fffecfbbda has no output cluster genOnOff

The device is operating in its expected no-neutral mode:

device_work_mode: Zigbee end device

I deleted the device from Zigbee2MQTT, factory-reset it, and paired it again. The interview again completed successfully, but the same configuration error occurred immediately afterward.

Despite the configuration error, normal relay functionality appears to work. Zigbee2MQTT receives ON/OFF state changes, including changes made with the physical button. Other exposed settings such as power_on_behavior and network_indicator also work.

@Koenkk @CubeZ2mDeveloper

What did you expect to happen?

I expected the ZBM5-1C-80/86 to complete configuration successfully when installed without a neutral wire and operating as a Zigbee end device.

If the output genOnOff cluster and the corresponding toggle action are unavailable in no-neutral/end-device mode, Zigbee2MQTT should skip that binding or make it conditional instead of failing the entire device configuration.

The device's normal relay functionality should remain available without a persistent configuration error.

How to reproduce it (minimal and precise)

1. Install a SONOFF ZBM5-1C-80/86 without a neutral wire.
2. Factory-reset the switch.
3. Enable permit join in Zigbee2MQTT.
4. Pair the switch.
5. Wait for the Zigbee interview to complete successfully.
6. Observe the automatic device configuration.

Result:

Device has no output cluster genOnOff

The device reports:

device_work_mode: Zigbee end device

Deleting, factory-resetting, and pairing the device again produces the same result.

Zigbee2MQTT version

2.12.1

Adapter firmware version

EmberZNet Revision: 7.5.1 [GA]

Adapter

Nabu Casa ZBT-2

Setup

Zigbee2MQTT is running as the Home Assistant Zigbee2MQTT app/add-on.

Host environment:

• Home Assistant installation type: Home Assistant OS
• Home Assistant OS: 18.1
• Home Assistant Core: 2026.7.4
• Supervisor: 2026.07.3
• Architecture: x86_64 / amd64
• Virtualization: KVM
• Machine type: OVA virtual machine
• Docker: 29.5.3
• Linux kernel: 6.18.37-haos
• Zigbee2MQTT is containerized by Home Assistant Supervisor.
• The ZBT-2 coordinator is passed directly to the Zigbee2MQTT container over USB.

Device database.db entry

No response

Debug log

[2026-07-28 21:22:43] info: z2m: Interviewing '0x4c97a1fffecfbbda'

[2026-07-28 21:22:51] info: z2m: Successfully interviewed '0x4c97a1fffecfbbda'

[2026-07-28 21:22:51] info: z2m:mqtt: MQTT publish: topic
'zigbee2mqtt/bridge/event', payload
'{"data":{"definition":{"description":"Zigbee Smart one-channel wall switch (type 80/86).","model":"ZBM5-1C-80/86","source":"native","supports_ota":true,"vendor":"SONOFF","version":"0.0.0"},"friendly_name":"0x4c97a1fffecfbbda","ieee_address":"0x4c97a1fffecfbbda","status":"successful","supported":true},"type":"device_interview"}'

[2026-07-28 21:23:01] info: z2m: Configuring '0x4c97a1fffecfbbda'

[2026-07-28 21:23:04] error: z2m: Failed to configure
'0x4c97a1fffecfbbda', attempt 6
(Error: Device 0x4c97a1fffecfbbda has no output cluster genOnOff
at getEndpointsWithCluster
(/app/node_modules/.pnpm/zigbee-herdsman-converters@26.76.0/node_modules/zigbee-herdsman-converters/src/lib/utils.ts:757:15)
at configure
(/app/node_modules/.pnpm/zigbee-herdsman-converters@26.76.0/node_modules/zigbee-herdsman-converters/src/lib/modernExtend.ts:286:54)
at Object.configure
(/app/node_modules/.pnpm/zigbee-herdsman-converters@26.76.0/node_modules/zigbee-herdsman-converters/src/index.ts:363:27)
at Configure.configure
(/app/lib/extension/configure.ts:135:13)
at Configure.onMQTTMessage
(/app/lib/extension/configure.ts:45:25)
at EventEmitter.wrappedCallback
(/app/lib/eventBus.ts:252:17))

[2026-07-28 21:23:04] info: z2m:mqtt: MQTT publish: topic
'zigbee2mqtt/bridge/response/device/configure', payload
'{"data":{},"error":"Failed to configure (Device 0x4c97a1fffecfbbda has no output cluster genOnOff)","status":"error","transaction":"n234g-5"}'

[2026-07-28 21:27:37] info: z2m:mqtt: MQTT publish: topic
'zigbee2mqtt/0x4c97a1fffecfbbda', payload
'{"detach_relay_mode":{"detach_relay_outlet1":"DISABLE","detach_relay_outlet2":"DISABLE","detach_relay_outlet3":"DISABLE"},"device_work_mode":"Zigbee end device","last_seen":"2026-07-28T21:27:37+03:00","linkquality":144,"network_indicator":false,"power_on_behavior":"previous","state":"OFF","update":{"installed_version":4100,"latest_release_notes":null,"latest_source":"https://raw.githubusercontent.com/Koenkk/zigbee-OTA/master/images/Sonoff/zbm5-120-zed_v1.0.4.ota","latest_version":4100,"state":"idle"}}'

[2026-07-28 21:32:01] info: z2m: Configuring '0x4c97a1fffecfbbda'

[2026-07-28 21:32:04] error: z2m: Failed to configure
'0x4c97a1fffecfbbda', attempt 7
(Error: Device 0x4c97a1fffecfbbda has no output cluster genOnOff)

[2026-07-28 21:32:04] info: z2m:mqtt: MQTT publish: topic
'zigbee2mqtt/bridge/response/device/configure', payload
'{"data":{},"error":"Failed to configure (Device 0x4c97a1fffecfbbda has no output cluster genOnOff)","status":"error","transaction":"u4xc1-1"}'

Notes

Device details:

• Manufacturer: SONOFF
• Model: ZBM5-1C-80/86
• Device firmware: 1.0.4
• Installed firmware version: 4100
• Hardware version reported through MQTT discovery: 16
• Wiring: no neutral
• Operating mode: Zigbee end device
• zigbee-herdsman-converters version shown in the stack trace: 26.76.0
• No OTA update is currently available.
• Link quality during testing was approximately 140–148.

The successful interview is followed by this configure error:

Error: Device 0x4c97a1fffecfbbda has no output cluster genOnOff
at getEndpointsWithCluster
(/app/node_modules/.pnpm/zigbee-herdsman-converters@26.76.0/node_modules/zigbee-herdsman-converters/src/lib/utils.ts:757:15)
at configure
(/app/node_modules/.pnpm/zigbee-herdsman-converters@26.76.0/node_modules/zigbee-herdsman-converters/src/lib/modernExtend.ts:286:54)
at Object.configure
(/app/node_modules/.pnpm/zigbee-herdsman-converters@26.76.0/node_modules/zigbee-herdsman-converters/src/index.ts:363:27)

The MQTT configure response is:

{
"data": {},
"error": "Failed to configure (Device 0x4c97a1fffecfbbda has no output cluster genOnOff)",
"status": "error"
}

Zigbee2MQTT exposes an action with the value "toggle" for this model. This suggests that the converter attempts to configure command-based genOnOff functionality even though the no-neutral/end-device variant does not expose the required output cluster.

Normal relay functionality works:

• Zigbee2MQTT and Home Assistant can switch the relay ON and OFF.
• Pressing the physical button produces ON/OFF state updates.
• The device continues reporting normally.
• power_on_behavior and network_indicator can be configured.

The problem therefore appears limited to the converter's output-cluster binding/configuration for this operating mode rather than pairing, signal quality, or basic relay control.

Start with configure in zigbee-herdsman-converters/src/lib/modernExtend.ts and getEndpointsWithCluster in src/lib/utils.ts, using the reported no-neutral ZBM5-1C-80/86 behavior as the reproduction. Verify how the converter handles the missing output genOnOff cluster and the toggle action. Done means configuration completes without this error while relay control and existing settings continue to work.