I bought a 2166 this fall, from a 1440 and keep getting this s1 error code when I hook the 1020 head up. I'm following the book I think. I hook everything up and then cycle the key, then drop the head all the way for a few seconds, then raise it and it stops on its way up like it says it will. After in continues to raise all the way up the s1 appears. The book says that it doesn't recognize the potentiameter. Does this mean it is bad, or what. I don't see any pinched wires. Doesn't the nob need to be all the way to the right? I even tried an old one off of neighbors head and didn't matter. Any help would be greatly appreciated.