POLAR 115EL Cutter, blade won't go up!

Hi,
I need some help, my Polar cutter knife goes down but then it get stock and it doesn't go up, it seems
like is a cycle problem. Has anyone ran into the same problem?
Thanks in advance

 

Hi sir
Good day
Hope you are well
Normally this since the Limit switchs b22a +b22b in gearbox :1)can be disadjustments, or broken, or loose wires, or contact very wear, you must examine very well, repair or replace. Of course you must see if the N.O(contacts normally open) they open, maybe is close or corroded the contacs and replace, and vice versa the N.C. use the Schematic Diagram 2) See if -42Vdc are going in Solenoid Bolt trought the Connector S sz-gb tight this connector very well, see if there are some loose wires, or broken Pin, or corroded pins

the Solenoid Bolt, can be Dirty, or sticky clean with Normal Graphite from pencil, Tight the wires very well 3) See if the plastic cam in gearbox is o.k or loose the Bolt, in there are in exact position for Knife goes up, adjust the N.C and N.O contact of limit switch 22a +22b.
4) Test the Relais d21a+d21b for -42Vdc see if there are NOT interruption in the line see his Schematic D.
Let me know any question or doubt