All I can tell you is, OLDER Kwikee the stop was in the Controller. Doug
NEW style 2005 and newer controller will not work with old style controller. It is cheaper to buy the Conversion kit than to buy the new style motor and Controller as separate parts. Just remember, you also have to change the Door pin switch whether magnetic or pin switch to work with new controllers. This part also comes in the conversion kit. Failure to replace the Door switch will result in reverse operation. When you test the newer step motors, the 2 wires going to the motor will go DEAD when the step motor is stuck or bad. This is stopped by the controller, otherwise the 2 small motor wires would heat up and melt.