Crankshaft Position Sensor: Description and Operation

Crank Angle Sensor:

N-SIGNAL SENSOR

PURPOSE
The N-signal is used to read crank angle and engine rpm. This signal is used for injection and ignition timing.

LOCATION
The signal generator is built into the distributor.

CONSTRUCTION
The sensor consists of a rotor (stator) and pick-up coil. Stator lobes are spaced at 120° to reference TDC of each cylinder.

OPERATION
A signal is generated whenever the engine is rotating. Each time a stator lobe passes the pick-up coil, a voltage pulse is generated. Due to lobe design, three pulses per revolution are produced. The pulses appear 120° apart, corresponding to TDC position of each cylinder.

G-SIGNAL SENSOR

PURPOSE
The G-signal is used to read cylinder #1 TDC. This signal is used to determine which cylinder is being referenced by the N-signal.

LOCATION
The signal generator is built into the distributor.

CONSTRUCTION
The sensor consists of a rotor (stator) and pick-up coil. The stator has a single lobe corresponding to cylinder #1 TDC.

OPERATION
A signal is generated whenever the engine is rotating. Each time a stator lobe passes the pick-up coil, a voltage pulse is generated. Due to lobe design, one pulse per revolution is produced. This pulse occurs only when cylinder #1 is at TDC.