Homing is an important part to get reliable positions. You should enable log and home and then send M114 to see where firmware think you are. Send G1 Xpos Ypos Zpos to see where firmware things that is.
Under some conditions you can also move unhomed if have allowed it and move away from 0 and endstops do not trigger or you do not leave printer volume. After a G1 S1 you can move all around without checks if endstops do not forbid it (test with M119) .
Check also values in eeprom, especially min coordinates and length of axis, steps per mm, acceleration, jerk, max feedrate. Wrong values there can cause unexpected results.