Crankshaft Position Timing Ring: Description and Operation

Crank Sensor & Toothed Gear:

Location and Construction
The CKPTR is attached to the crankshaft and has 57 symmetrically spaced rectangular segments around its periphery.

Operation
These segments induce a signal in the reluctance coil when the engine is running, the frequency of the signal being proportional to engine speed. Three omitted segments, which would give a total segment complement of 60, interrupt the induced signal to provide crankshaft position references.