UENR0623-02 53 Engine Operation controls the pressure in the fuel rail by using this valve to control the amount of fuel that enters the chambers in the pump. Supply Voltage – The supply voltage is a continuous voltage that is supplied to a component in order to provide the electrical power that is required for the component to operate. The power may be generated by the ECM or the power may be battery voltage that is supplied by the engine wiring. System Configuration Parameters – System configuration parameters are parameters that affect emissions and/or operating characteristics of the engine.
Illustration 47 g00284479 Rated Fuel Limit – This is a limit that is based on the power rating of the engine and on the engine rpm. The Rated Fuel Limit enables the engine power and torque outputs to conform to the power and torque curves of a specific engine model. These limits are in the flash file and these limits cannot be changed. T Harness – This harness is a test harness that is designed to permit normal circuit operation and the measurement of the voltage simultaneously. Typically, the harness is inserted between the two ends of a connector. Reference Voltage – Reference voltage is a regulated voltage and a steady voltage that is supplied by the ECM to a sensor.
The reference voltage is used by the sensor to generate a signal voltage. Throttle Position – The throttle position is the interpretation by the ECM of the signal from the throttle position sensor or the throttle switch. Throttle Position Sensor – The throttle position sensor is an electronic sensor that is usually connected to an accelerator pedal or a hand lever. This sensor sends a signal to the ECM that is used to calculate desired engine speed. Relay – A relay is an electromechanical switch. A flow of electricity in one circuit is used to control the flow of electricity in another circuit.
A small current or voltage is applied to a relay in order to switch a much larger current or voltage. Throttle Switch – The throttle switch sends a signal to the ECM that is used to calculate desired engine speed. Secondary Speed/Timing Sensor – This sensor determines the position of the camshaft during engine operation. If the primary speed/timing sensor fails during engine operation, the secondary speed/ timing sensor is used to provide the signal. Top Center Position – The top center position refers to the crankshaft position when the engine piston position is at the highest point of travel. The engine must be turned in the normal direction of rotation in order to reach this point.
Sensor – A sensor is used to detect a change in the pressure, in the temperature, or in mechanical movement. When any of these changes are detected, a sensor converts the change into an electrical signal. Wait To Start Lamp – This is a lamp that is included in the cold starting aid circuit in order to indicate when the wait to start period has expired. The glow plugs have not deactivated at this point in time. Short Circuit – A short circuit is a condition that has an electrical circuit that is inadvertently connected to an undesirable point. An example of a short circuit is a wire which rubs against a vehicle frame and this rubbing eventually wears off the wire insulation.
Electrical contact with the frame is made and a short circuit results. Warning Lamp – The warning lamp is used to warn the operator of the presence of an active diagnostic code. Wastegate – This is a device in a turbocharged engine that controls the maximum boost pressure that is provided to the inlet manifold. Signal – The signal is a voltage or a waveform that is used in order to transmit information typically from a sensor to the ECM. Wastegate Regulator – The wastegate regulator controls the pressure in the inlet manifold to a value that is determined by the ECM.
The wastegate regulator provides the interface between the ECM and the mechanical system that regulates inlet Suction Control Valve (SCV) – The SCV is a control device in the high-pressure fuel pump. The ECM