SHIM PACK 9P1921 - Caterpillar

Overview
These engines are equipped with an electronic control system. The system consists of a computer, sensors, and software. The system provides these capabilities:
Control of the engine
Control of particulate emissions via the "Caterpillar Regeneration System" (CRS)
Interface with the vehicle
Fault detection and reportingEngine Control
The engine's computer is called the Electronic Control Module (ECM). The ECM monitors inputs from various sensors and inputs from the vehicle in order to control the engine.The ECM contains a flash file. The flash file is the software for the ECM. The flash file contains the operating maps. The operating maps define the following characteristics of the engine:
Horsepower
Torque curves
Engine speed (rpm)Refer to Troubleshooting, "System Overview" for additional information on the electronic control system."Caterpillar Regeneration System" (CRS)
The CRS contains these components:Diesel Particulate Filter (DPF) - A DPF is installed in the vehicle's exhaust system. The DPF collects soot and ash from the engine's exhaust.Aftertreatment Regeneration Device (ARD) - The ARD provides additional heat to the engine's exhaust in order to convert the soot in the DPF into gas. The ARD operates only when additional heat in the exhaust is needed.Software - Software in the ECM monitors the DPF and the ARD. The software controls the delivery of fuel, combustion air, and spark to the ARD.Vehicle Interface
The ECM interfaces with the vehicle via an electrical connector on the ECM. The interface is configurable. This allows the control system to support a variety of vehicles and applications.Inputs - The vehicle provides inputs to the electrical connector on the ECM in order to indicate the status of switches and other controls. The ECM must be correctly configured in order to properly interpret the inputs. The ECM is configured via the Caterpillar Electronic Technician (ET). Refer to Troubleshooting, "Programmable Input Parameters" for additional information on configuring the inputs.Outputs - The ECM provides outputs for the vehicle via the electrical connector in order to control lamps, solenoids, and other devices. The ECM must be correctly configured in order for the outputs to match the vehicle's configuration. Refer to Troubleshooting, "Programmable Output Parameters" for additional information on configuring the outputs.Fault Detection and Reporting
The ECM monitors inputs from the sensors and inputs from the vehicle. Software in the ECM interprets the inputs. The software determines if the inputs are operating correctly. A Diagnostic Trouble Code (DTC) is activated when the software detects a problem with an input.The ECM broadcasts the codes on two data links. The data links are ATA and J1939. Cat ET must communicate on both data links in order to fully service the engine.The codes can be displayed on Cat ET and optional displays in the vehicle's cab. Refer to Troubleshooting, "Diagnostic Trouble Codes" for additional information on diagnostic trouble codes and a complete list of codes.