There are two cables from the left side motor. A 4-wire stepper motor cable...

and a 3 wire limit switch cable.

Follow these wires back to the control board. Take a picture of how they are connected for reference.

Notice the 4 wire cable is connected to the left stepper. Make a note of the colors and their orientation. The extension cables might not be a perfect color match and we don't want to reconnect them backwards.

Notice the left limit switch cable is connected to the X- pin. Again, take note of the color and orientation.

With power off, gently disconnect the limit switch cable and the stepper motor cable. Pull straight out from the board. Pull from the black connector, not the wire.