The Elevator would have to be programmed to accept the procedure you have described. Some Elevators when depressing the Door Close will cancel the Door Timing and the door will close. Most high rise Elevators have load weighing devices to measure the weight of the Elevator with and with out passengers. This comes in handy when you have a bank of elevators and traffic is at it's peak so if an elevator has enough passengers another elevator is dispatched and so on. The key is an independent service key that will override and give you independent service of the elevator when activated.