My friend has a 2000 ZR sno pro and his APV valves arnt working right. He bought the sled used. He only rode it maybe 50 miles and the left piston melted. After we fixed it we were putting the APV valve servo motor back on and now they wont work right. Whenever we start the sled the cable mounting drum osolates or goes back and forth a few times and then spits the cables right out. We went to the local cat dealer and they said that most likly the servo's bad, and its quite a bit of money to replace it. I was wondering if anyone has had the same problem and how they fixed it. Also, is it possible to test the controller for the servo? Because it would be a waste to buy a new servo and find out the controller is bad, and that the $300 servo is fine.