ER31 Error with PETG and new print core

[amiedoubled 0]

Hi. I have a S5, a brand new AA .40mm print core and Ultimaker PETG Fluorescent Yellow filament. I’ve  updated the firmware on the printer but I’m still receiving a ER31 error about half way through my prints and they keep failing.

 

Next troubleshooting steps? 

[gr5 2,069]

Try the other AA core.  It's usually the core and you should have an extra.  That's the first debugging step.  Sometimes (rare on the S5) it can be the cable that goes into the print head.

 

It's trivial to remove the rear 2 screws on the print head - they are very long.  Access them from above.  Once removed, the rear half of the print head comes off easily.  Inside is a connector.  Make sure the connector is seated well.  Don't try to pull the connector out without watching a video about it first.  fbrc8.com and ultimaker have nice videos about how to access this connector.