When does a CAS white PASSENGER DOOR message turn amber if the passenger door is open?

The CAS white PASSENGER DOOR message turns amber when the left engine run switch is moved from the OFF position to the RUN position because this action indicates a transition from a non-operational to an operational state for the engine, which directly affects the aircraft's systems and safety protocols. In this case, an open passenger door could pose a serious risk during engine operations, and changing the engine run switch prompts the aircraft's systems to re-evaluate the status of critical safety features, thus triggering the amber warning to alert the crew.

Other options are based on conditions that do not trigger a change in the status of the CAS message. For instance, cruising altitude, increasing cabin altitude, or exceeding a certain airspeed do not inherently relate to whether the passenger door is open or closed in the context of engine operation; hence, they do not activate the amber warning for the passenger door.