Yes, the controller is a potentiometer. It gives you complete control from no power assist to full power. At full power there is almost no feedback in the wheel. I found that about 50% power feels great. Just enough that you can steer with one arm and yet still feel what the wheels are doing. Here is a link to the control unit on ebay.
Saturn Vue ion Chevrolet Equinox â€“ Electric Power Steering Controller Box â€“ Epas | eBay