locate the control valve for the actuator by lisening forthe exhausted air from low / reverse. this is con troled by two solenoids check these for power suply and earth. if ok the coils may be at fault. disconect the air feed to the actuator and see if air is being suplied to the air cylender. If ok the seals in the actuator are leaking.if not the coils may be at fault.or the valve may be stuck. good luck!!
Jon Boy
January 2010