Grand Cherokee 2WD L6-4.0L VIN S (1997)
Camshaft Position Sensor: Description and Operation
CAMSHAFT POSITION SENSOR
The camshaft position sensor is located in the distributor.
The sensor contains a hall effect device called a sync signal generator to generate a fuel sync signal. This sync signal generator detects a rotating
pulse ring (shutter) on the distributor shaft. The pulse ring rotates 180 degrees through the sync signal generator. Its signal is used in conjunction
with the crankshaft position sensor to differentiate between fuel injection and spark events. It is also used to synchronize the fuel injectors with
their respective cylinders.
When the leading edge of the pulse ring (shutter) enters the sync signal generator, the following occurs: The interruption of magnetic field causes
the voltage to switch high resulting in a sync signal of approximately 5 volts.
When the trailing edge of the pulse ring (shutter) leaves the sync signal generator, the following occurs: The change of the magnetic field causes
the sync signal voltage to switch low to 0 volts.
CIRCUIT OPERATION
The Powertrain Control Module (PCM) supplies 5 Volts to the camshaft position sensor (in distributor) on circuit K25. Circuit K25 connects to
cavity A17 of the PCM.
The PCM receives the camshaft position sensor signal on circuit K24. Circuit K24 connects to cavity A18 of the PCM.
The PCM provides a ground for the camshaft position sensor signal (circuit K24) through circuit K4. Circuit K4 connects to cavity A4 of the
PCM.
