Positive Battery - This pertains to any of the harness wiring which is part of the circuit that connects to the positive battery post.
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 fault, a fault must be on hold and a fault 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.
Connector Contact - A connector contact is the component that actually makes the electrical connection between the harness connector and another connector plug.
Detected Fault - This is a fault that has been found by the ECM. The fault is recorded and diagnostic information is available in the service mode.
Diagnostic - Diagnostic pertains to the showing, monitoring, and/or recording of information other than the normal operation. Diagnostic information is available when the ECM is in service mode.
Display - The display consists of the readout and the indicators. These types are visible on the window of the Caterpillar Monitoring System.
ECM - ECM is the acronym that is used to signify the electronic control module.
Fault - A fault is a failure of a component in an ECM system. The ECM detects a fault when a signal at the ECM connector is outside a valid range. An FMI and a CID identify the type of fault.
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 two digit number that the ECM has assigned to a particular attachment code for a particular machine. 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) - An MID is a diagnostic code that identifies the ECM which diagnosed the fault. The three-digit code is displayed in the display area of the Caterpillar Monitoring System, when the machine is in the service mode. The MID for the power train ECM is 081.
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 inputs to the ECM. 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. The positive 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 input to the ECM, which is expecting a ground signal, an open signal or a positive 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 positive 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.
Hard Wired - Hard wired refers to a permanent electrical connection that is made between two components. These soldered or crimped connections are not meant to be altered.
Continuity - Continuity refers to a continuous path.
Pulse Width Modulated (PWM) - A PWM signal is a signal in which the duty cycle varies according to the machine conditions that are monitored. The frequency of a PWM signal is constant.