Crankshaft Position Sensor: Description and Operation

Typical Crankshaft Position (CKP) Sensor:

Waveforms:

The crankshaft timing is read by a Variable Reluctance Sensor (VRS), triggered by a 36 minus 1 tooth trigger wheel. This wheel is located inside the front cover.


The sine wave type signal generated by this sensor is called a Variable Reluctance Sensor signal (VRS). The VRS signal provides two types of information. one is the position of the crankshaft in 10 degree increments. The other is engine rpm or crankshaft speed.


The EDIS module uses this information with the spark advance information from the EEC-IV module to determine ignition coil turn on time.


Base timing is set at 10 +/- 2 degrees BTDC, with the crankshaft sensor as reference, and is not adjustable.