Pixhawk4 buzzer flows mV not 5V

I am trying to use a separate RTK GPS rather than the GPS provided by Pixhawk4.
Pixhawk4 uses the drone’s buzzer and switch for the GPS terminal. I connected the GPS pins, the switch pin, and the buzzer pin as shown in the figure below, and the GPS was connected well.

But the buzzer and switch don’t work. The pinout of Pixhawk4 says 5V flows to the + pin of the buzzer, but it was confirmed that 0.1~0.2V was flowing when actually measured.
I was expecting 5V to flow just by connecting it, but I’m disappointed it doesn’t. Why doesn’t 5V flow? What additional work do I need to do?

How do you know the switch does not work?
The buzzer pin would not have +5 unless the buzzer is on

@jimdgit The LED on the switch does not work, and the arming does not release when pressed.
I know it’s not 5V when the buzzer doesn’t sound.
The problem is that 5V does not come out when the buzzer should sounds. When I checked with an oscilloscope at the timing when the buzzer should sound, 0.1~0.2mV was measured.