The bolt, a component which allows the cabin doors to be locked. This seems to indicate a problem with the doors, more precisely when closing them, but not necessarily with the bolt itself.
A problem with locking the doors on the fourth floor was identified when the order to move was given. In fact, at that moment, the elevator control card programs a default waiting time to ensure that the locking has been carried out correctly. If the time is exceeded, it is considered a fault.
The technician therefore goes straight up to check the state of the locks of the landing doors and those of the cabin, and realizes that the door movement rollers are very worn over time. This prevents the door from closing all the way and therefore the electrical contact of the lock does not activate on the fourth floor, indicating a latch fault on the Field® application.
The technician was therefore able to replace the roller directly to resolve the problem, before it turned into a more serious failure. 😇