The crankshaft and camshaft pick up signals are sent direct to the PCM which
decides the proper coil pack to ﬁre.
You can figure at cranking what the hertz should be by what it is at these speeds.
Crankshaft Pick Up:
Pin #21, wire color is white-red.
Camshaft Pick Up:
Pin #85, wire color is white-violet.
Crankshaft Pick Up Signal
Frequency At Idle 470-530 Hz
Frequency At 55 MPH 1350-1460 Hz
Camshaft Pick Up Signal
Frequency At Idle 5-7 Hz
Frequency At 55 MPH 17-21 Hz
Here's the diagram for the system.