What else to try for this "pull out the filament" error?

[Shpigford]

Last night during a long print I had a poop chute backup that ultimately cancelled the print.

Now today, I keep getting this error on a multi-color, AMS print.

I’ve disassembled and cleaned the extruder. Done hot and cold pulls 3 times on the hotend, and tried different filaments.

Every time I start the print, it goes through the full initialization process, prints the “Flow Dynamics Calibration” lines and then throws this error about the filament.

Interestingly, the AMS appears to disconnect as well (red lights flashing and “AMS not connected” message in the slicer. But it happens at the exact same point each time (after the flow dynamics bit).

I’m stumped.

X1C w/ AMS using Bambu Lab Matte PLA.

[lasermike]

Not sure why the AMS is saying it’s disconnected but there are a whole bunch of filament present sensors between the feed tower and the extruder. I wonder if one or more are jammed. There is one in the hub on the back, 4 in the hub underneath the AMS and one in each feed tower plus the one in the extruder. I found that the one in the extruder can be jammed against the housing even without any bits of filament in there.
Ima toot my own horn and post a link to this thread. Scroll down for my posts, I shared a few links to the wiki that seem to be well liked. Maybe it can help.