FixVault

Manual 3rd

WARNING: This page is about a different car, the 2016 Mazda CX-3. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Blower Fan Speed Control Signal Waveform (Manual 3rd)
G10910318Courtesy of MAZDA MOTORS CORP.

Climate control unit terminal 

Oscilloscope setting 

Vehicle condition