What is the function of the hydraulic switch in AUTO mode?

In AUTO mode, the hydraulic switch is designed to control the operation of the hydraulic pump based on the aircraft's bus power and the position of the flaps. This functionality ensures that the hydraulic system operates efficiently and only when necessary, which helps preserve energy and manage the hydraulic pressure effectively. By coordinating the pump activity with the flap position and bus power, the system can adapt to the aircraft's operational status, optimizing performance and safety during various phases of flight.

The other responses do not accurately describe the function of the hydraulic switch in AUTO mode. For instance, if the pump were to run continuously regardless of conditions, it would lead to unnecessary energy use and potential overheating of the system. Similarly, if the pump only started when the engine was off, it would not provide the required hydraulic support during critical moments when the flaps are being deployed. Operating at a lower pressure setting isn't the primary function of the hydraulic switch; rather, it is to manage the timing and conditions under which the pump operates.