Each interrupter ring has blades and
windows that either block the magnetic field or allow it to close one of
the Hall effect switches. The outer Hall effect switch produces a signal
called the CKP 18X because the outer interrupter ring has 18 evenly
spaced blades and windows. The CKP 18X portion of the crankshaft
position sensor produces 18 ON - OFF pulses per crankshaft revolution.
The Hall-effect switch closest to the crankshaft, the CKP Sync portion
of the sensor, produces a signal that approximates the inside interrupter
ring. The inside interrupter ring has 3 unevenly spaced blades and
windows of different widths. The CKP Sync portion of the crankshaft
position sensor produces 3 different length ON - OFF pulses per
crankshaft revolution. When a CKP Sync interrupter ring window is
between the magnet and inner switch, the magnetic field will cause
the CKP Sync Hall effect switch to ground the CKP Sync signal voltage
supplied from the ignition control module. The CKP 18X interrupter
ring and Hall-effect switch react similarly. The ignition control
module interprets the CKP 18X and CKP Sync ON - OFF signals as an
indication of crankshaft position, and the ignition control module
must have both signals to fire the correct ignition coil. The ignition
control module determines crankshaft position for correct ignition
coil sequencing by counting how many CKP 18X signal transitions occur,
i.e.; ON - OFF or OFF - ON, during a CKP Sync pulse.
The camshaft position sensor is located on the timing cover behind the
water pump near the camshaft sprocket. As the camshaft sprocket turns, a
magnet in it activates the Hall effect switch in the camshaft position
sensor. When the Hall-effect switch is activated, it grounds the
signal line to the ICM, pulling the camshaft position sensor signal
circuit's applied voltage low. This is interpreted as a CMP Sensor
signal. The CMP Sensor signal is created as piston #1 is approximately
25 degrees after top dead center on the power stroke.