Could be but both yours are C-techs and they change regularly as you can see by the revision numbers on the tags. They update designs based on suppliers, quality and so pretty regularly. I have had great results with c-tech products. You can call c-tech and ask them, it is possible. The machine did not work before you changed sticks correct ? I would check the toggle switch for the lift/drive function inside the box first. The steering function uses its own two micro switches independent of lift/drive that is depend on that particular toggle switch to power up the coils for either lift or drive on the function manifold. I would not suspect a failed diode since you don't have either function. Each function has its own separate wiring, relay etc depending on what side of the switch is active. Check that toggle switch first make sure its getting power and is switching power between functions.