D 150 Pickup V6-239 3.9L (1992)
Crankshaft Position Sensor: Description and Operation
Crankshaft Position Sensor Operation 3.9L
LOCATION
The sensor is located on the bellhousing of the transmission.
PURPOSE
The signal from the Crankshaft Position Sensor is used to determine crankshaft angle, engine speed, and basic timing.
The engine controller also uses the signal from the Crankshaft Position Sensor combined with the input signal from the camshaft position sensor to
properly synchronize injection.
OPERATION
The crankshaft position sensor is a hall effect switch that detects notches on the flywheel/drive plate.
The notches cause a pulse to be generated when they pass through the switch. The pulses are input to the engine controller. For each engine
revolution there are 3 groups of 2 pulses and 3 groups of 1 pulse generated.
If engine controller does not sense input from the crankshaft position sensor, engine controller will deactivate ASD and fuel pump relay,
interrupting voltage to fuel pump, fuel injectors, and ignition coil, causing a no start condition.