S250 aux hydro problem

Hi, have a 08 s250 with acs controls. My issue is with my grapple bucket attachment. When I hit the thumb control one side goes up the other does not. After hitting it a few times one will go up and then the other will but they will go down slowly on there own. Then one will power up and power down while the other will not do anything. Sometimes a code will come up 40-13. Left joystick not in neutral. I wiggle it and code comes off but still doesn't fix my problem. I've checked the bucket on another machine and the bucket is fine. Any help would be much appreciated.