Specifications

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Rising or Falling edge?
Mag Sensor Falling Edge Polarity
When viewing the waveform on a labscope, the direction of travel of the voltage line as it crosses the 0v line determines the sensors active edge. This edge will not
deviate in time with respect to RPM. The opposite edge will. This corresponds to the point at which the trigger tooth passes the center of the sensor.
Mag Sensor Rising Edge Polarity
Pole Diameter
It is important to remember when designing a trigger wheel with a mag sensor, that the width of the tooth in
degrees should be no less than 1 times the width of the pole piece in degrees and no more than 2 times this
number of degrees. Some mag sensors have a stainless steel shield on them making it difficult to see the true pole
diameter. Rub the sensor in some steel shavings to give you an idea of the pole piece size.
To know for sure if you sensor produces a rising or a falling
edge you need a Digital Volt/Ohm Meter or DVOM.
Disconnect the ECU from the Harness. Plug the red lead
of the meter into the signal terminal of the ECU Header
and the black lead to the 0v terminal. Place a steel object
(like a screwdriver) against the sensor. Set the DVOM to
read DC volts. Quickly remove the metal from the sensor
and watch the direction the voltage goes either positive or
negative. If the voltage goes negative, the sensor is a falling
edge sensor. If the voltage goes positive, the sensor is a
rising edge signal.