Inspection Using an Oscilloscope (Reference)

WARNING: This page is about a different car, the 2010 Mazda 3. However, it is still accessible from the selected car via links, so may be relevant.

Intruder sensor signal

Terminal connected: 5N (+)-Body ground (-)
Oscilloscope setting: 5 V/DIV (Y): 5 s/DIV (X), DC range

Fig 1: Oscilloscope Waveform Graph (Intruder Sensor Signal)
Courtesy of MAZDA MOTORS CORP.