Cannot configure default E step for extruder on TH3D
Initializing

After changing your firmware, you always need to overwrite the old values in the SRAM and EEPROM with those from the Firmware. Which you do with M502 &amp; M500:


  Installing firmware does not by itself alter the EEPROM, so these settings needed to be seeded into SRAM via M502 and then saved into EEPROM via M500.


You could also run a G-code that has only these two lines:

M502
M500


Altering the EEPROM

Via command

Alternatively, you could access the printer via a terminal and send the command M92 E415 to overwrite the SRAM directly, then M500 to save the new setting to EEPROM. The associated G-code that only alters the E-steps/mm would read

M92 E415
M500


Via Software

Or you use a terminal that supports direct alteration of the EEPROM, like Repetier Host.