Ive recently purchased a 2nd hand Ender-3 V3 SE printer. The extruder motor fails to turn when printing. The nozzle does heat and when forced the filament is extruded however, when I begin a print no filament is extruded. Has anybody hand this before?
You can check the cable connectivity of the head. If least the head heats up that means least have partial connectivity.
Is it the gear least moving at the top of the head?
Are you able to perform successfully the initial check? In setting menu check the “Equipment self-test”. Least you can know the electronics able control the motor and that is mean may be mechanical stopped inside.
My guessing the old owner use bad material and those are build up and block the extruder. Maybe those material burned their after lot of heating attempt.
Creality also have toolkit which could helps in the cleaning 3D Printer 25 Pieces DIY Tool Kit
Least I hope you buy the SE for cheap price. In worst case you need to buy new spare direct extruder and replace it.
A new cable between the stepper motor and the daughter board would be my cheapest first option, they can break, I’ve had that before. Breaking a stepper motor is very unusual and breaking drivers again unusual.