Alert Indicator - An alert indicator is an indicator on the Computerized Monitoring System. When a problem exists the indicator flashes. The associated pictograph symbol identifies the abnormal machine system.
+Battery - This pertains to any of the harness wiring which is part of the circuit that connects to the positive battery post.
+V - +V is a constant voltage that is supplied to a component. This voltage provides electrical power for the component's operation. +V is provided by an electronic control module or the battery.
Caterpillar Electronic Technician (ET) - This is a diagnostic service tool for a personal computer (PC).
Clear - This pertains to removing diagnostic information from the memory of the ECM. Before clearing a diagnostic code, a diagnostic code must be on hold and the diagnostic code must not be present.
Component Identifier (CID) - A CID is a code that is used to identify a particular component. The CID is a four digit code that is shown on the ECM display when the ECM is in service mode or normal mode.
Configuration Harness Code - The configuration code tells the ECM the important characteristics of the machine it is installed on. The hydrostatic transmission ECM receives the configuration code directly from the configuration harness code plug.
Connector Contact - A connector contact is the component that actually makes the electrical connection between the harness connector and another connector plug. Connector contacts are either pins or sockets.
Data Event - A data event is recognition of the occurrence of abnormal machine operation. When a combination of signals arrive at the ECM, the ECM decides when the machine is operating abnormally. Data events are remembered by the ECM and data events are viewed using a service tool.
Detected diagnostic code - This is a diagnostic code that has been found by the ECM. The diagnostic code is recorded and diagnostic information is available in the service mode.
Diagnostic - This pertains to the showing, monitoring and/or recording of information other than normal. Diagnostic information is available when the ECM is in service mode.
Display - The display consists of the readout and the indicators. These are visible through the window of the ECM.
ECM - ECM is the acronym for electronic control module.
Electronic Control Analyzer Programmer (ECAP) - This is a service tool which helps diagnose electronic control systems.
Event - Whenever the ECM records information it is called an event. The ECM categorizes the events into either a diagnostic code event or a data event.
Diagnostic Code - A diagnostic code is a failure of a component in an ECM system. The ECM detects a diagnostic code when a signal at the ECM connector is outside a valid range. An FMI and a CID identify the type of diagnostic code.
Floating - The status (state) of an ECM input that is not connected to a positive source or ground.
Failure Mode Identifier (FMI) - An FMI is a diagnostic code that identifies the type of failure that has occurred. The FMI consists of a decimal point "." and two digits. This code is shown on the ECM display when you are in service mode or normal mode.
Harness Code - The harness code provides the characteristics of the machine such as the size of the engine, idle speed, tire size and attachments. The Caterpillar Monitoring System uses the data link to provide the harness code to the ECM. The ECM operates on different machines, but the ECM must know the characteristics of the machine.
Hold or On Hold - This pertains to the holding of diagnostic information that is shown in the display area when the ECM is in the service mode. It is necessary to hold the set of diagnostic information before troubleshooting or clearing.
Jumper - A jumper is a piece of wire that is used to make an electrical connection during troubleshooting.
Machine Code - The machine code is a number that consists of two digits. The machine code is assigned to a particular harness code for a particular machine by the ECM. The machine code is shown on the message display when the machine is in the Self Test Mode. Each sales model has a specific harness code. Therefore, each sales model also has a specific machine code.
Module Identifier (MID) - A MID is a code that identifies the ECM which diagnosed the diagnostic code. The three-digit code is displayed in the display area of the Caterpillar Monitoring System when the machine is in the service mode.
Present - This pertains to the status of a diagnostic code. The diagnostic code is currently active when the diagnostic code is present.
Problem - Problem refers to the presence of an abnormal machine condition. For example; low engine oil pressure or high hydraulic oil temperature.
PWM - A PWM signal is a signal in which the duty cycle (time on verses time off) varies according to the machine conditions that are monitored. The frequency of a PWM signal is constant.
Sales Model Harness Code - The harness code tells the Caterpillar Monitoring System the characteristics of the model it is installed on, such as: engine size, idle speed and attachments. The monitor uses the data link to communicate the harness code to the other ECM's on the machine. This information is necessary because the ECM's can operate on different sales models.
Scroll - When you scroll through information in the display area, all available sets of diagnostic information are shown by one set at a time. A set of diagnostic information is shown briefly. Then, the display automatically advances to the next set. After all sets have been shown, the display shows "END". Then, the sets are repeated.
Service Code - A service code describes a condition in an electrical system. This code is stored in the ECM for the service technician.
Show - This pertains to information that is shown on the ECM display that is viewed by the operator or a service person.
Signal - Signal pertains to the condition of the ECM inputs. A ground signal has continuity with the frame ground. An open signal is not connected to the frame ground and the voltage is approximately 5 DCV. A +battery signal is at the same voltage as the battery (25 to 30 DCV).
Signal Wire - The signal wire is the harness wire that connects the sensor or the switch to the ECM.
Switch Input - Switch input is any ECM input which is expecting a ground signal, an open signal or a +battery signal.
System Voltage - System voltage is the actual voltage that exists between the positive battery post and the frame ground. System voltage is also known as +battery voltage.
Undetected Fault - This is a fault that is not detected by the ECM, but the fault is found by the operator or by a service technician.