COVER AS-REAR 4610461 - Caterpillar

Illustration 1 g01858875
Pump, Electronics, and Tank Unit (PETU) - The PETU is a module that controls the injection of Diesel Exhaust Fluid (DEF) into the exhaust gas stream. The module consists of a DEF storage tank, a pump, a filter, a Voltage Load Protection Module (VLPM), a Dosing Control Unit (DCU), and a DEF heating system.Rated Fuel Limit - The rated fuel limit 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.Reference Voltage - Reference voltage is a regulated voltage that is supplied by the ECM to a sensor. The reference voltage is used by the sensor to generate a signal voltage.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.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.Selective Catalytic Reduction (SCR) - SCR is a process for reducing the oxides of nitrogen (NOx) in the exhaust gases. Ammonia is introduced into the exhaust and reacts with the exhaust gases in the SCR catalyst to convert the NOx into nitrogen and water vapor.Sensor - A sensor is a device that is used to detect the current value of pressure or temperature, or mechanical movement. The information that is detected is converted into an electrical signal.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 results in a short circuit.Signal - The signal is a voltage or a waveform that is used in order to transmit information typically from a sensor to the ECM.Suction Control Valve (SCV) - The SCV is a control device in the high-pressure fuel pump. The valve controls the pressure in the fuel rail by varying 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. The power may be generated by the ECM or the power may be battery voltage that is supplied by the engine wiring.Suspect Parameter Number (SPN) - The SPN is a J1939 number that identifies the specific component of the electronic control system that has experienced a fault.System Configuration Parameters - System configuration parameters are parameters that affect emissions and/or operating characteristics of the engine.Tattletale - Certain parameters