SUPPORT AS 3955741 - Caterpillar

Engine Speed Sensor
Illustration 1 g00507191
Engine Speed Sensor
The engine speed sensor is located on the flywheel housing. An AC voltage is produced as the gear teeth of the flywheel pass the tip of the sensor. The frequency of the voltage is proportional to the speed of the gear teeth as the teeth pass the tip of the sensor. The controller uses this signal to make decisions for the hydraulic pump and the engine.Pressure Sensor
Illustration 2 g00685436Pump Discharge 1 (Drive) and Pump Discharge 2 (Idle)
These sensors send a signal to the controller. The controller will use the signal to modify the following items:
Adjusting the horsepower
Changing the travel speed
Determining light load and "AEC" level 1