Delivery pile not moving up or down

Hi everyone, Speed Master 74-5 printing machine delivery table moves a little and then does not move up or down. No error message is displayed on the screen. If you want the pile to move a little, you have to turn the machine off and on again. Can anyone help me solve this? I have been trying everything for four days. Thank you.

 

Make sure the sensor on drive side of delivery is not damaged.clean all barrier sensors on the delivery

 

Which year is this machine fabrication ??

 

Which year is this machine fabrication ??

 

Problem with
1) motor encoder
2) stk/bak card
3) is feeder pile moving ok???

 

Hi, I have the same problem on my PM74-2 (2003), how did you manage to solve it?