extruder heats to 190 bed to 55 then printer starts printing extruder temp drops to 187 and cold extrusion error displays and printer stops extruding…
only just started was printing excellently… any ideas
Sounds you have dropouts in the Hotend thermistor line.
Make sure the wiring is ok and the thermistor is well isolated in the heater block.
cheers,
Christian
Are there any major dips on the temp graph?
I checked resistance at the hotend connection to controller board 100k tried wiggling wires remained the same. so no loose connection .
there is only small temp fluctuations in the temp and now the heater-bed temp drops up and down by 1 to 2 degrees as well .
Is the thermistor properly mounted.
What version of the hot end do you have?
The default value for cold extrusion error is below 170°. So it’s curious you get it at 187°.
Check the value in the Marlin firmware (configuration.h).
1 or 2° variation is normal. More than 5 isn’t.
If you experience big variations, you can adjust the PID factor : PID Tuning