Motor reverse

what 2 wires do I switch to reverse the motor

Stepper motors may be reversed in a number of different ways:

  • swap the left and right pair of wires
  • reverse the ordering of the wires in the left or the right pair
  • reverse all four wires

A typical stepper have four wires, forming two pairs - one for each coil inside the stepper.
You can identify which form a pair by measure resistance or continuity.

Swapping any ONE pair around will reverse the direction of the stepper.