Crankshaft Sensor

Crankshaft sensor contains a pick-up coil. A signal plate (rotor) is mounted on the crankshaft pulley. As the crankshaft rotates, protrusions on the signal plate pass near the pick-up coil. This induces AC voltage in the pick-up coil. The ECM senses the AC voltage, and uses it to determine engine speed and crankshaft position.

The ECM may use input signals for determining ignition timing (spark advance) and for controlling fuel injection system, idle speed control system, EGR system (ES300), heated oxygen sensor system and intake air control valve system.