Usually only a building's maintenance supervisor and the local emergency services will be issued an emergency elevator key. These keys override the elevator system; when an elevator stalls or stops, the key can also be used to reset the system, which can resolve the problem. No unauthorized user should use the emergency elevator key; in some places, it is considered a criminal act. Some places require an elevator key to be located in a certain place known to emergency personnel.
Find the key switch on the elevator call panel. Usually this will only be found on the call panel of the building's main floor.
Insert the key. Turn the key to either "bypass" or "reset" and hold for a few moments to allow the control system to reset.
Return the key to the off position. Remove key. Test for resumed functioning by pressing the up button. The elevator should respond normally.