[Bug] AMS 2 Pro Drying Action Error

[sneak-it]

Home Assistant Version

2025.11.2

Bambu Lab Integration Version

v2.2.16

Describe the bug

When attempting to use the new drying action, drying does not start. Using a P1S and AMS 2 Pro via LAN mode. Logs below.

Seems like a simple validation error, expecting AMS 2 and not AMS 2 Pro:

ha-bambulab/custom_components/bambu_lab/coordinator.py

Line 442 in 47a412f

if (model != 'AMS 2') and (model != 'AMS HT'):

I'm able to walk up to the printer and start drying manually via interface.

To Reproduce

1. Developer Tools
2. Actions
3. Choose Start Filament Drying
4. I chose: AMS 2 Pro, 65c, Unchecked Rotate, Duration in hours 12 hours
5. Begin

Expected Behaviour

Expected drying to begin.

What device are you using?

P1S

Diagnostic Output

2025-11-29 12:38:59.051 DEBUG (MainThread) [custom_components.bambu_lab] handle_service_call: start_filament_drying
2025-11-29 12:38:59.052 ERROR (MainThread) [custom_components.bambu_lab] Passed device is not an AMS 2 or AMS HT.
2025-11-29 12:38:59.052 DEBUG (MainThread) [custom_components.bambu_lab] Service call complete.

Log Extracts

Logger: custom_components.bambu_lab
Source: custom_components/bambu_lab/coordinator.py:443
integration: Bambu Lab (documentation, issues)
First occurred: 12:38:59 PM (1 occurrence)
Last logged: 12:38:59 PM

Passed device is not an AMS 2 or AMS HT.

Other Information

Device Info:
AMS 2 Pro
by Bambu Lab
Connected via P1S
Firmware: 02.00.19.68
Hardware: N3F05

[AdrianGarside]

https://github.com/greghesp/ha-bambulab/releases/tag/v2.2.17-beta1

[sneak-it]

https://github.com/greghesp/ha-bambulab/releases/tag/v2.2.17-beta1

Thank you for the update!

Updated to 2.2.17-beta1, restarted HA.

Attempted to run drying again, I'm met with a MQTT error:

2025-12-03 13:52:48.027 DEBUG (MainThread) [custom_components.bambu_lab] handle_service_call: start_filament_drying
2025-12-03 13:52:48.027 DEBUG (MainThread) [custom_components.bambu_lab.pybambu] Sent {'print': {'sequence_id': '0', 'command': 'ams_filament_drying', 'ams_id': 0, 'temp': 45, 'cooling_temp': 45, 'duration': 6, 'humidity': 0, 'mode': 1, 'rotate_tray': False}} to topic device/redactedserial/request
2025-12-03 13:52:48.027 DEBUG (MainThread) [custom_components.bambu_lab] Service call complete.
2025-12-03 13:52:53.732 DEBUG (P1S-Mqtt-161) [custom_components.bambu_lab.pybambu] Updating HMS error list.
2025-12-03 13:52:53.732 WARNING (P1S-Mqtt-161) [custom_components.bambu_lab.pybambu] HMS ERRORS: {'1-Code': 'HMS_0500_0500_0001_0007', '1-Error': 'MQTT Command verification failed. Please update Studio (including the network plugin) or Handy to the latest version, then restart the software and try again.', '1-Wiki': 'https://wiki.bambulab.com/en/x1/troubleshooting/hmscode/0500_0500_0001_0007', '1-Severity': 'fatal', 'Count': 1}
2025-12-03 13:52:53.733 DEBUG (MainThread) [custom_components.bambu_lab] EVENT: HMS errors: {'device_id': 'redactedid', 'name': '', 'type': 'event_printer_error', 'code': 'HMS_0500_0500_0001_0007', 'error': 'MQTT Command verification failed. Please update Studio (including the network plugin) or Handy to the latest version, then restart the software and try again.', 'url': 'https://wiki.bambulab.com/en/x1/troubleshooting/hmscode/0500_0500_0001_0007'}

P1S Firmware: 01.09.00.00
AMS 2 Pro Firmware: 02.00.19.68

Did some searching, this is because of the newer firmware? I have LAN mode enabled.

[AdrianGarside]

You'll have to be in developer lan mode with the 1.09 firmware. I thought I was already checking that and throwing an error before trying to send the command though.

[AdrianGarside]

Yes, it shouldn't get to that point:

    if write_action:
        if self.get_model().print_fun.mqtt_signature_required:
            LOGGER.error("Printer firmware requires mqtt encryption. All control actions are blocked.")
            self._report_encryption_enabled_issue(True)
            return False

[sneak-it]

You'll have to be in developer lan mode with the 1.09 firmware. I thought I was already checking that and throwing an error before trying to send the command though.

Got it, missed the developer setting. That's changed and everything is working, thanks so much!

Interesting that I never saw that logger error though.

[sneak-it]

Sorry for the follow up again, was finally able to test the actual drying part with LAN mode and developer lan enabled:

2025-12-05 18:41:37.488 DEBUG (MainThread) [custom_components.bambu_lab] handle_service_call: start_filament_drying
2025-12-05 18:41:37.489 DEBUG (MainThread) [custom_components.bambu_lab.pybambu] Sent {'print': {'sequence_id': '0', 'command': 'ams_filament_drying', 'ams_id': 0, 'temp': 65, 'cooling_temp': 45, 'duration': 6, 'humidity': 0, 'mode': 1, 'rotate_tray': False}} to topic device/01P00C560700065/request
2025-12-05 18:41:37.490 DEBUG (MainThread) [custom_components.bambu_lab] Service call complete.

but drying does not begin.

[AdrianGarside]

I think other people in the original thread reported the command didn’t work with their P1S. You may be out of luck.

[sneak-it]

Found it - #1448

Thanks again.