X1 Front Housing Fan not working - No HMS errors

Hi there,

I am looking for some knowledge and advice on debugging this issue.

The part cooling fan in the Front Housing Assembly does not rotate when instructed by a print g-code or the manual command (touch screen, handy app or Studio).

Despite the printer being relatively new (05-2023), it is possible to have a faulty fan; however, what surprises me is the absence of any HMS error message such as:

https://wiki.bambulab.com/en/x1/troubleshooting/hmscode/0300_0400_0002_0001

** Debug/Solving process (in progress) **

  • I searched in the wiki and official communication hubs for similar problems. I only found a few, and mainly related to loosening cables.

  • Hardware verification:

Following BL wiki procedures, I checked fan movements, cable siting, also using a magnifier lens and microprobes. I checked if the cables were broken and tested continuity at each cable and connector pins. I did this for the six-pin cable, which connects the Front Housing board and the TH board, and the four-pin wires between the fan and the Front housing board. Additionally, the front housing led, and tachymeter is fully functional.

  • Ordered a new front house assembly - if not faulty, it will go to stock parts;

** Software/Firmware **

  • I verified the slicer settings regarding cooling and even the g-code, which entails the correct instruction to move the fan.

  • Upgraded and downgraded between the three available versions of the firmware and repeated the tests;

  • Carry out a factory reset;

  • After all these tests without any finding, I open a trouble ticket.
    For that, I did some printing tests and recorded them in video.
    During one of the tests, I received the following HMS alert:

https://wiki.bambulab.com/en/x1/troubleshooting/hmscode/0300_0F00_0001_0001

  • I followed the recommended procedure in detail and found that, at least visually, both USB-C and AP-MC cables were in proper condition and perfectly seated at the connectors.
  • I ordered a new USB-C cable just in case;
  • The other likely cause is firmware, so I downgrade to the older version of the printer firmware yet with any changes. Note: the HSM error was already gone before downgrading the firmware. I ran the device self-testing program before and after the firmware update, which resulted in no errors.

Does anyone have similar issues? Am I missing any detail? Thank you.