3176C, 3196 & 3406E MARINE ENGINES Caterpillar

SECTION 7: Glossary of Terms

Usage:

Glossary Of Terms

Active Diagnostic Code: Describes a condition that is currently present to alert the driver or service technician of an abnormal engine operation parameter. Refer to Diagnostic Code.
After Market Device: As used here, a device or accessory installed by the customer or vessel OEM after the engine is delivered.
Air-To-Air Aftercooler (ATAAC): A means of cooling inlet air after the turbocharger, using ambient air for cooling. The inlet air is passed through an aftercooler (heat exchanger) mounted in front of the radiator before going to the inlet manifold.
Alternating Current (AC): The direction of current flow changes (alternates) regularly and constantly in a circuit.
American Wire Gauge (AWG): A measure of the diameter (and therefore the current carrying ability) of electrical wire. The smaller the AWG number, the larger the wire.
Atmospheric Pressure Sensor: Analog sensor generates a signal proportional to atmospheric (barometric) air pressure in the crankcase and sends a signal to the ECM.
Boost Pressure Sensor: This sensor measures inlet manifold air pressure from the turbocharger and sends a signal to the ECM.
Breakout T Harness: A test harness designed to connect into a machine or engine harness which allows normal circuit operation while providing a breakout or T to measure signals.
Bypass Circuit: A circuit, usually temporary, to substitute for an existing circuit, typically for test purposes.
Calibration: As used here, is an electronic adjustment of a sensor signal.
Caterpillar Engine Monitoring: The part of the Caterpillar Electronic Engine Control that monitors Coolant Temperature, Oil Pressure, Inlet Manifold Air Temperature and Coolant Level to alert the operator of detected problems. The Coolant Temperature, Inlet Manifold Air Temperature, and Oil Pressure Sensors are supplied by Caterpillar and monitored by the ECM. The Coolant Level Sensor is OEM installed, but still monitored by the ECM. After market engine monitoring systems do not interface with the Caterpillar Electronic Engine Control.
Check Engine Lineup: Sometimes referred to as the "Diagnostic Lamp", it is used to alert the operator of the presence of an active event and is used to flash a diagnostic code.
Code: Refer to Diagnostic Code.
Cold Mode: A mode of engine operation where the timing is retarded and the low idle may be raised for engine protection, reduced smoke emissions and faster warm up time.
Component Identifier (CID): Two or three digit code which is assigned to each component to identify data via data link to ECM.
Coolant Level Sensor: This OEM installed sensor detects the absence/presence of coolant at the probe and sends a signal to the ECM.
Coolant Temperature Sensor: This sensor detects the engine coolant temperature for Cold Mode operation and Caterpillar Engine Monitoring (if Engine Monitoring is not programmed OFF).
Customer Specified Parameter: A parameter value that can be changed and whose value is set by the customer.
Data Link: A two-wire electrical connection for communication with other microprocessor based devices such as Caterpillar electronic monitoring displays. The data link is also the serial communication medium used for programming and troubleshooting with Caterpillar Electronic Service Tools.
Desired RPM: An input to the electronic governor within the ECM. The electronic governor uses inputs from the Throttle Position Sensor, Engine Speed/Timing Sensor and Customer Parameters to determine "Desired RPM".
Diagnostic Code: Sometimes referred to as a diagnostic fault code. These codes indicate an electronic system malfunction or problem with the engine electronic system.
Diagnostic Flash Code: These codes are flashed out using the Check Engine/Diagnostic Lamp to indicate an electronic system malfunction or an event detected by the Electronic System.
Diagnostic Lamp: Sometimes referred to as the "check engine light", it is used to warn the operator of the presence of an active diagnostic code.
Direct Current (DC): The type of current where the direction of current flow is consistently in one direction only.
Duty Cycle: Refer to Pulse Width Modulation.
Electronically Controlled Unit Injector: The injection pump which mechanically actuated, electronically controlled unit injector combining the pumping, electronic fuel metering and injecting elements in a single unit.
Electronic Control Analyzer & Programmer (ECAP): An electronic service tool developed by Caterpillar used for programming and diagnosing a variety of Caterpillar electronic controls using RS-232 data link.
Electronic Control Module (ECM): The engine control computer that provides power to the engine electronics. It accepts inputs that monitor and outputs that control or change to act as a governor to control engine rpm.
Electronic Engine Control: The complete electronic system that monitors and controls engine operation under all conditions.
Electronic Technician (CAT ET): A software program to run on a service tool like a personal computer (PC). This program will supplement and eventually replace ECAP.
Event Code: These codes (EID) indicate an event that describe an abnormal engine condition, such as an Idle Occurrence. They are not necessarily (or usually) an indication of problems within the Electronic System.
Failure Mode Identifier (FMI): Type of failure the component experience (adopted from SAE standard practice J1587 diagnostics).
Flash Code (FC): The Caterpillar proprietary code numbers which are flashed out on the diagnostic lamp (or Check Engine Light).
Flash Programming: A way of programming or updating an ECM with an Electronic Service Tool over the data link instead of replacing components.
Fuel Ratio Control (FRC): FRC Fuel Pos. - is a limit based on control of the fuel to air ratio and is used for emissions control purposes. When the ECM senses a higher boost pressure (more air into cylinder), it increases the "FRC Fuel Pos" limit (allows more fuel into cylinder).
Fuel Position: An internal signal within the ECM, from the Electronic Governor to Fuel Injection Control. It is based on Desired RPM, FRC Fuel Position, rated fuel position and engine rpm.
Fuel Pressure Sensor: This sensor detects the fuel pressure of the fuel transfer pump. The ECM will diagnose low fuel pressure and activate a Warning Lamp and log the event in memory.
Fuel Temperature Sensor: This sensor detects the fuel temperature. The ECM monitors the fuel temperature and adjusts calculated fuel rate accordingly.
Full Load Setting (FLS): Number representing fuel system adjustment made at the factory to "fine tune" the fuel system maximum fuel delivery. Correct value for this parameter is stamped on the engine information ratings plate. This parameter must be programmed or a Diagnostic Code 253-02 Check Customer Or System Parameters (56) will be generated.
Full Torque Setting (FTS): Similar to Full Load Setting. This parameter must be programmed or a Diagnostic Code 253-02 Check Customer Or System Parameters (56) will be generated.
Harness: The wiring bundle (loom) connecting all components of the Electronic System.
Hertz (Hz): Measure of frequency in cycles per second.
Inlet Manifold Air Temperature Sensor: This sensor detects the inlet manifold air temperature. The ECM monitors the inlet air temperature and coolant temperature to adjust injection timing. It is also part of Caterpillar Engine Monitoring.
Integrated Electronic Controls: The engine is designed with the electronic controls as a necessary part of the system. The engine will not operate without the electronic controls.
Logged Diagnostic Codes: Describes codes which are stored in memory. They are meant to be an indicator of possible causes for intermittent problems. Refer to Diagnostic Code.
Transmission Oil Temperature Sensor: The ECM monitors Transmission oil temperature with the sensor up to 120°C (248°F).
Transmission Oil Pressure Sensor: The ECM monitors Transmission oil pressure with a sensor located on the high pressure side of the Transmission from 0 kPa (0 psi) to 3100 kPa (442 psi).
Oil Pressure Sensor: This sensor measures engine oil pressure and sends a signal to the ECM and is part of Caterpillar Engine Monitoring.
Open Circuit: Condition where an electrical wire or connection is broken or a switch is open, so that the signal or the supply voltage can no longer reach its intended destination.
Original Equipment Manufacturer (OEM): As used here, the customer or manufacturer of a machine or vessel in which a Caterpillar engine is installed.
Parameter: A programmable value or limit which determines the characteristics or behavior of the engine and/or machine.
Password: A group of numeric or alphanumeric characters, designed to restrict access to parameters. The electronic system requires correct passwords in order to change certain engine specifications (Factory Passwords). Passwords are also required to clear certain diagnostic codes.
Personality Module or Ratings Personality Module: The module attached inside of the ECM which contains all the instructions (software) for the ECM and performance maps for a specific power family.
Pulse Width Modulation (PWM): A signal consisting of variable width pulses at fixed intervals, whose ratio of "TIME ON" versus total "TIME OFF" can be varied (also referred to as "duty cycle").
Rated Fuel Position: ("Rated Fuel Pos" on ECAP) - this indicated the maximum allowable fuel position (longest injection pulse). It will produce rated power for this engine configuration.
Reference Voltage: A regulated, unchanging voltage supplied by the ECM to a sensor. The reference voltage is used by the sensor to generate a signal voltage.
Remote Mounted Throttle Position Sensor: This sensor measures throttle position and sends a signal to the ECM. The sensor is mounted off of the throttle assembly. The throttle is connected directly to an electronic sensor (which is not adjustable). Refer to Throttle Position Sensor.
Sensor: A device used to detect and convert a change in pressure, temperature, or mechanical movement into an electrical signal.
Service Program Module (SPM): A software program on a factory programmable computer chip, designed to adapt an Electronic Service Tool to a specific application.
Short Circuit: A condition where an electrical circuit is unintentionally connected to an undesirable point. Example: a wire which rubs against an metallic object until the insulation is worn through and the wire makes contact.
Signal: A voltage or waveform used to transmit information typically from a sensor to the ECM.
Speed "burp": A sudden, brief, unwanted change in engine rpm.
Speed/Timing Sensor: Provides a Pulse Width Modulated Signal to the ECM, which the ECM interprets as crankshaft position, direction of rotation and engine rpm and sends the signal to ECM.
Subsystem: As used here, it is a part of the Electronic System that relates to a particular function, for instance throttle subsystem, etc.
Supply Voltage: A constant voltage supplied to a component to provide electrical power for its operation. It may be generated by the ECM, or it may be vessel battery voltage supplied by the vessel wiring.
System Configuration Parameters: Parameters which affect power rating family or emissions.
Throttle Position: The ECM interpretation of the signal from the Throttle Position Sensor.
Throttle Position Sensor: An electronic sensor which is connected to an accelerator pedal or a hand lever and sends a Pulse Width Modulated Signal to the ECM.
Timing Calibration: The adjustment of an electrical signal as a means of correcting timing error between the crankshaft and camshaft. Refer to Speed/Timing Sensor.
Total Tattletale: Total number of changes to all Customer Specified Parameters stored in the ECM.
Warning Lamp: Used to warn the operator of the presence of a Caterpillar Engine Monitoring detected problem.