Cause:
- the motor shortcircuit contactor is not detected as opened at the start of travel
- the motor shortcircuit contactor is not detected as closed at the end of travel
- the auxiliary contact of the motor shortcircuit contactor does not switch
Remedial action:
- check the contactor monitoring
- check the wiring of the motor shortcircuit contactor
- check the supply voltage of the motor shortcircuit contactor 
- check the supply voltage of the motor shortcircuit contactor monitoring 
- check the "CO" parameter in the "Monitoring" menu