Engine Speed Sensor: Description and Operation

Reference Pulse Circuit:

PURPOSE
The Engine Speed Sensor is a camshaft driven pickup which informs the ECM/TCM of engine rpm.

OPERATION
The Engine Speed Sensor is supplied with a 5 volt reference by the ECM/TCM. The sensor relays 4 pulses back to the ECM/TCM per engine revolution. As the number of revolutions increase, so does the number of pulses. By interpreting the number of pulses the ECM/TCM can monitor the engine speed.

LOCATION
The Engine Speed Sensor is mounted at the center rear of the engine.