Crankshaft Position Sensor: Description and Operation

The crankshaft position sensor (1) is mounted in the right rear of the engine block, below the turbocharger, behind a heat shield. This sensor is used to detect engine speed.

The crankshaft position sensor is a magnetic pickup type sensor that generates an A/C signal. The sensor contains a permanent magnet and a coil of wire. The sensor generates an A/C signal each time a notch in the reluctor wheel on the crankshaft passes across the permanent magnet. The ECM calculates engine speed based on the frequency of the A/C signal.