I have a Otis. 311 on route. Front and rear opening. Rear opening serves 1 floor On fire service and independent service door won't reopen after I release door close button. I can view the input dropping out when I release button. Any ideas?

Do you only have 1 cop? You should have 2 door open buttons, one for each door

What happens when you let up on the button? If the doors continue to close, there may be a parameter that controls how FS and IND operate. You can set the close operation to close with just the initiation of the door close on some controllers. If you don't do anything, do the doors stay open? If the doors just stop, will the open button move them? Could be a bad output module or IO for Door Open. We need more information.

They continue to close. If there is a parameter that controls it I haven't been able to find it. The doors should close with constant pressure on button until fully closed. If I let up on door close button (this is on the rear door only) the doors should reopen. The front doors work properly. 2 COPs both have front and rear open and close buttons. Front doors work properly from both COPs.

2 COPs both have front and rear open and close buttons. Front side works correctly from both COPs

Compare front fire service parameters to rear and see if there are any differences. Check all fire service modes (certain cities have different fire service reqs) Is DOL going to proper state allowing reopen? Does door reopen if open button is pressed? On FS and IND? Do you have any buddies that wear green in Adjustor positions to ask??