Basic Information:
Printer Model: Voron 2.4
MCU / Printerboard: Manta M8P
Host / SBC: CB1/EBB36/U2C
klippy.log
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Describe your issue:
I recently replaced the stealthburner on the Voron with an A4T toolhead. Noted changes:
Switched from TAP to Beacon Rev.H
Using 5V pin on probe port to power hotend fan (was VIN on FAN1 port for 24v fan on stealthburner) - using same PA0 pin to control fan ground - works fine. All other connections to EBB36 are the same as before.
I have tried and read everything I can find to figure out why communication to the toolhead is lost at pretty much the exact same point in prints which is within a few seconds of extruder movement. It is not a random point in the print at all.
Things I have tried:
Rebuilt can bus harness
Moved U2C usb cable direct to pi - was connected to a hub
Replaced and squeezed contacts on 120R jumper to ensure good contact
Moved extruder stepper wires away from EBB36 as much as possible
Updated Klipper and all MCU’s to latest firmware versions
Uninstalled camera and crowsnest
Updated all other add-ins - mainsail, moonraker, klipperscreen
Monitored PSU voltage throughout print startup sequence - stays right at 24V up until and after communication loss
I’m pretty confident in the integrity of the can bus cable connections from the U2C to the EBB36. I was very careful when rebuilding the cable. I’ve had issues with Micro-Fit connections and movement flexing in the past but the print failures were a lot more random with those issues and I had finally solved them with better crimping tools and awareness to connection terminals quality.
At this point I’m prepared to try a different toolhead board whether it be another EBB36 or something different but I’m afraid there is something obvious that I am somehow missing. The fact that all the logs I have gone over pretty much show the same error seem to indicate I might be overlooking something obvious. Hoping someone has an idea. The printer ran flawlessly before this.
klippy-052725-4.log (1.6 MB)