RAM 2500 Truck 2WD V10-8.0L VIN W MDC (1999)
Crankshaft Position Sensor: Description and Operation
CRANKSHAFT POSITION SENSOR
Crankshaft Position Sensor Location
The crankshaft position sensor is located on the right-lower side of the cylinder block, forward of the right engine mount, just above the oil pan
rail.
Crankshaft Position Sensor Operation
The crankshaft position sensor detects notches machined into the middle of the crankshaft.
There are five sets of notches. Each set contains two notches. Basic ignition timing is determined by the position of the last notch in each set of
notches. Once the powertrain control module (PCM) senses the last notch, it will determine crankshaft position (which piston will next be at Top
Dead Center). An input from the camshaft position sensor is also needed. It may take the module up to one complete engine revolution to
determine crankshaft position during engine cranking.
The PCM uses the signal from the camshaft position sensor to determine fuel injector sequence. Once crankshaft position has been determined, the
PCM begins energizing a ground circuit to each fuel injector to provide injector operation.
CRANKSHAFT POSITION SENSOR-PCM INPUT
This sensor is a hall effect device that detects notches in the engine crankshaft.
It is used to indicate to the powertrain control module (PCM) that a spark and or fuel injection event is to be required. The output from this sensor,
in conjunction with the camshaft position sensor signal, is used to differentiate between fuel injection and spark events. It is also used to
synchronize the fuel injectors with their respective cylinders.
