And the explanation of how the motor reverses is simple enough with the diagram as pictured by our illustrious repairman: What happens deep within the timer is this: The polarity is reversed ! Picture your cheater cord as shown by RM running the motor. To reverse the flow as shown you would only need to do 2 things. 1st allow the motor to come to a complete halt. Then flip the cheater cord over and plug it in again. What happens is exactly the same as before, but the poles are now reversed. What happens? The motor runs the same as before only it does it in the reverse direction. Your timer is the means for reversing polarity. It is as simple as that.