Crankshaft Position Sensor: Description and Operation

Crankshaft Position Sensor Location:

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 crankshaft position sensor combined with the input signal from the camshaft position sensor to properly synchronize fuel injection.





OPERATION
The crankshaft position sensor is a hall effect switch that detect notches on a pulse ring mounted to the crankshaft.

The notches cause a pulse to be generated when they pass under the sensor. The pulses are input to the PCM. For each engine revolution there are 5 groups of 2 pulses generated.

Crankshaft position is determined during cranking. Once the last slot of a set has been detected, crankshaft position can be determined by combining crankshaft and camshaft position input. This process may take up to one complete crankshaft revolution.

If the PCM does not sense input from the crankshaft position sensor, PCM will deactivate the automatic shutdown relay and fuel pump relay, interrupting voltage to fuel pump, fuel injectors, and ignition coil, (no start condition).

CIRCUIT OPERATION
The Powertrain Control Module (PCM) supplies 8 volts to the crankshaft position sensor on circuit K7. Circuit K7 connects to cavity 7 of the PCM.

The PCM receives the crankshaft position sensor signal on circuit K24. Circuit K24 connects to cavity 24 of the PCM.

The PCM provides a ground for the crankshaft position sensor (circuit K24) through circuit K4. Circuit K4 connects to cavity 4 of the PCM connector.