Crankshaft Position Sensor: Description and Operation

PURPOSE
The signal from the Crankshaft Position (CKP) Sensor is used to determine crankshaft angle, engine speed, and basic timing.

Powertrain Control Module (PCM) also uses the signal from the CKP Sensor combined with the input signal from the Camshaft Position (CMP) Sensor to properly synchronize injection.

The sensor is located on the bellhousing of the transmission.

Crankshaft Position Sensor Operation:

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 PCM. The flywheel/driveplate has 8 single notches spaced every 45 degrees. For each engine revolution there are 8 single pulses generated.

NOTE: If PCM does not sense input from the crankshaft position sensor, PCM will deactivate Automatic Shutdown (ASD) and fuel pump relays, interrupting voltage to fuel pump, fuel injectors, and ignition coil, causing a no start condition.