VALVE GP-SOLENOID 2704437 - Caterpillar

Throttle Switch Input Circuit
Desired engine speed is selected by the operator by using a ten position switch that is mounted in the cab area. The switch consists of four poles that connect to four switch inputs on the ECM through the vehicle wiring. Each pole is read as "grounded" or "open" by the ECM. The ECM compares the pattern of "grounded" or "open" switch poles to a preprogrammed table in memory in order to select the desired engine speed.Automatic Engine Speed Control (AESC)
The AESC switch allows the operator to enable the automatic engine speed control. The AESC system reduces engine speed to 1350 rpm when the operator has not moved a hydraulic control for four seconds. The AESC switch also acts as a backup for the throttle switch.User Defined Shutdown Circuit
The ECM reads this switch input. The ECM will terminate the fuel injection if the input is connected to the chassis ground. The shutdown is permanently recorded in the ECM as a logged event.Aftercooler Temperature Input Circuit
The aftercooler temperature sensor is located in the elbow for the aftercooler at the rear of the engine. The sensor receives a 13 volt supply voltage from the ECM. The sensor produces a 5000 Hz PWM signal. The signal's pulse width is interpreted by the ECM as aftercooler temperature.Gear Box Temperature Input Circuit
The gear box temperature sensor is located in the pump drive case at the rear of the engine. The sensor receives a 13 volt supply voltage from the ECM. The sensor produces a 5000 Hz PWM signal. The signal's pulse width is interpreted by the ECM as gear box oil temperature.Demand Control Fan System Output Circuit
The demand fan control provides a 0 to 1.8 amp signal to the solenoid valve that controls the oil flow to the fan drive motor. A 1.8 amp signal sets oil flow in the fan drive to minimum resulting in minimum fan speed. Conversely, a 0 amp signal sets oil flow in the fan drive to maximum resulting in maximum fan speed. The ECM reads the engine coolant temperature sensor in order to control the fan speed.Injector Output Circuits
An electrical signal from the ECM controls each electronic unit injector (EUI). This electrical signal determines the fuel injection timing. The duration of the electrical signal determines the quantity of fuel that is injected. The signal allows precise control of the injectors.Atmospheric Pressure Input Circuit
Atmospheric pressure is monitored by the atmospheric pressure sensor. The sensor is located on the mounting bracket for the ECM. A 5.0 0.5 VDC supply voltage is provided by the ECM. The output of the atmospheric pressure sensor is a DC signal. This signal has a range from 0.2 volts to 4.8 volts. The ECM interprets the output voltage as atmospheric pressure.Turbocharger Inlet Pressure Circuit
The air pressure in the air induction system for the engine is monitored by the turbocharger inlet pressure sensors. The sensors are located in each air inlet tube. The ECM provides the sensor with a 5.0 0.5