Crankshaft Position Sensor: Description and Operation

Crank Sensor & Toothed Gear:

PURPOSE
The sensor provides the ECU with both engine speed and crankshaft position information.

OPERATION
When engine is running, timing ring segments induce a signal in the reluctance coil. Signal frequency is interpreted by the ECU as engine speed.

Induced signal interruptions caused by the 3 missing segments provide the ECU with crankshaft position references.

CONSTRUCTION
The sensor consists of a variable reluctance pick-up coil and a toothed gear (timing ring) turned by the crankshaft. There are 57 rectangular segments (teeth) around the gear circumference and 3 missing segments (a total of 60 symmetrically spaced divisions).

LOCATION
Front of engine at crank pulley.