# Eddy Probe installation breaks serial **URL:** \ **Category:** Eddy Sensor\ **Tags:** firmware\ **Created:** [April 23, 2026, 2:40pm UTC](https://forum.sovol3d.com/t/eddy-probe-installation-breaks-serial/9910 "2026-04-23T14:40:32Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![newhinton](https://avatars.discourse-cdn.com/v4/letter/n/d6d6ee/32.png) [@newhinton](https://forum.sovol3d.com/u/newhinton)\ **Post date:** [April 23, 2026, 2:40pm UTC](https://forum.sovol3d.com/t/eddy-probe-installation-breaks-serial/9910/1 "2026-04-23T14:40:32Z")
Hi! I am currently installing the Eddy-Probe-Kit from sovol. However, after installing and rebooting the printer, it is stuck at `"system booting"/"mcu 'mcu': Unable to connect"`. The klippy log indicates that the serial-device cannot be found. Checking via ssh reveals a single serial device. (I would expect 2) I did unplug the extruder head entirely and rebooted it, and it still only showed one serial port. This leads me to think the extruder is the one missing. I reflashed it again, no change. I did flash the 7.22 binary from their google drive linked in the wiki, and now it shows up with a new serial id, but the printer is still stuck. (this is half expected due to the changed serial id) Now, how do i proceed here? can i just run the 2.4.9 deb as the manual says, or do i need to do something else? ---
**Author:** ![mich0111](https://yyz2.discourse-cdn.com/flex030/user_avatar/forum.sovol3d.com/mich0111/32/1176_2.png) [@mich0111](https://forum.sovol3d.com/u/mich0111)\ **Post date:** [April 23, 2026, 3:02pm UTC](https://forum.sovol3d.com/t/eddy-probe-installation-breaks-serial/9910/2 "2026-04-23T15:02:11Z")
Hello, I recommend that you contact Sovol by email at [info@sovol3d.com](mailto:info@sovol3d.com). Be sure to include your order number and describe the issue. Best regards ---
**Author:** ![cardoc](https://avatars.discourse-cdn.com/v4/letter/c/ec9cab/32.png) [@cardoc](https://forum.sovol3d.com/u/cardoc)\ **Post date:** [April 23, 2026, 9:58pm UTC](https://forum.sovol3d.com/t/eddy-probe-installation-breaks-serial/9910/3 "2026-04-23T21:58:09Z")
> [@newhinton](#): > > Now, how do i proceed here? can i just run the 2.4.9 deb as the manual says, or do i need to do something else? I would try the .deb package (check your hardware version) That said the printer.cfg exracted from the 4mm .deb files has the exact same serial addresses as the origonal version, ```auto [mcu] serial: /dev/ttyACM1 restart_method: command [mcu extra_mcu] serial: /dev/ttyACM0 restart_method: command ``` I don’t recall ever dealing with address issues on a SV08. Is there a second usb\<\>serial on the toolhead board or does the one on the mainboard handle 2 serial ports? I always thought the communication to the toolhead was USB but it could be RS232 (serial). ---
**Author:** ![newhinton](https://avatars.discourse-cdn.com/v4/letter/n/d6d6ee/32.png) [@newhinton](https://forum.sovol3d.com/u/newhinton)\ **Post date:** [April 25, 2026, 7:48am UTC](https://forum.sovol3d.com/t/eddy-probe-installation-breaks-serial/9910/4 "2026-04-25T07:48:44Z")
I am not entirely sure what happened. It started working after another reflash and then just turning it back on after i left it for a few hours alone. It just came up then, but not immediately after. ---
**Author:** ![cardoc](https://avatars.discourse-cdn.com/v4/letter/c/ec9cab/32.png) [@cardoc](https://forum.sovol3d.com/u/cardoc)\ **Post date:** [April 25, 2026, 5:34pm UTC](https://forum.sovol3d.com/t/eddy-probe-installation-breaks-serial/9910/5 "2026-04-25T17:34:54Z")
> [@newhinton](#): > > I am not entirely sure what happened. You are not the only one who has had a reflash work. There is a thread someplace where the OP had to set the transfer speed in STtools to the lowest setting. My guess is the (clone) STlink Sovol provides is not of the highest quality.