The current wiring has GND->COM1, NO1->MOTOR-, MOTOR+->12V. To make it go backward, I would connect MOTOR+->GND and MOTOR-->12V . I have 2 relays with 3 pins each. Each relay can reswitch one thing to one of two other things when switched. The currently relay has ground, so I could make it wire ground to MOTOR+ when the other way. Then the other relay would have 12V, and could wire it to either MOTOR+ or MOTOR- . But, in that arrangement there would be no way to turn the motor off. Maybe it makes more sense to undo the wires and move them by hand. I'm thinking that I will need to do this again, though. But, it's easier to be physically near the motor when sending it in reverse.