Vehicle Speed Output (To Instrument Cluster)

ABS HU/CM terminal: Q (+) - AA (-)
Oscilloscope setting:
1. 1 V/DIV (Y), 5 ms/DIV (X), DC range
Vehicle condition: Driving 30 km/h (18.6 MPH)
NOTE: As vehicle speed increases, period of wave shortens.

Fig 1: Vehicle Speed Output Oscillations To Instrument Cluster
Courtesy of MAZDA MOTORS CORP.