It is this code in Printer.cpp around line 959:

if (

#if MIN_EXTRUDER_TEMP > 20

(Extruder::current->tempControl.currentTemperatureC < MIN_EXTRUDER_TEMP && !Printer::isColdExtrusionAllowed() && Extruder::current->tempControl.sensorType != 0)

#endif

fabs(com->E) * extrusionFactor > EXTRUDE_MAXLENGTH) {

p = 0;

destinationPositionTransformed[E_AXIS] = currentPositionTransformed[E_AXIS] = 0;

} else {

destinationPositionTransformed[E_AXIS] = 0;

currentPositionTransformed[E_AXIS] = -convertToMM(com->E);

}

destinationSteps[E_AXIS] = 0;

currentPositionSteps[E_AXIS] = -p;

} else {

if (

#if MIN_EXTRUDER_TEMP > 20

(Extruder::current->tempControl.currentTemperatureC < MIN_EXTRUDER_TEMP && !Printer::isColdExtrusionAllowed() && Extruder::current->tempControl.sensorType != 0) ||

#endif

fabs(p - currentPositionSteps[E_AXIS]) * extrusionFactor > EXTRUDE_MAXLENGTH * axisStepsPerMM[E_AXIS]) {

currentPositionSteps[E_AXIS] = p;

destinationPositionTransformed[E_AXIS] = currentPositionTransformed[E_AXIS] = convertToMM(com->E);

} else {

destinationPositionTransformed[E_AXIS] = convertToMM(com->E);

}

destinationSteps[E_AXIS] = p;

}

As you see the prevent here is only dependent on EXTRUDE_MAXLENGTH.

With which software do you send the moves? Maybe the software also has a protection preventing gcode form being send? So check log/console what gets send.