I’m working on an old Otis B Base 5 stop duplex.
On one car, it closes the doors when the c.o.p. Inspect switch is turned on for hoistway access. You can open the doors by holding the door open button, but the doors close as soon as you let off the button and the light curtain does not reopen the doors. This car has a newer Otis belt drive door operator. I’m having a difficult time determining where the “door close” signal is coming from.

Also both cars close the doors when Independent service is on or when the in car stop switch is on stop. Independent service will work, but to get the cars to run on independent the door close button has to be pressed after the doors are physically closed. Calls will latch with the stop switch in the stop position, but it doesn’t run until the switch is turned back to run. The door open button and breaking the light curtain both reopen the doors.

I have hit a wall and would appreciate and help or direction
Thanks!
Joe