DDEC III/IV Single ECM Troubleshooting

Section 4.8 Explanation of Abbreviations and Terms

Section 4.8
Explanation of Abbreviations and Terms

The following abbreviations and terms listed in Table "Abbreviations and Terms" , will be used throughout the electrical flowcharts.‪

Abbreviations‪

Terms‪

AAT‪

Ambient Air Temperature — calculated via the TCI temp sensor‪

A/C‪

Air Conditioning‪

ACG‪

Air Compressor Governor‪

ACLS‪

Add Coolant Level Sensor‪

A/D‪

Analog to Digital: The computer inside the ECM uses an A/D converter to convert a sensor voltage into a number with which the computer can work.‪

AFRS‪

Air Filter Restriction Sensor‪

ASR‪

Anti-Skid Regulation: Data supplied by the ECM for use with ABS (anti-lock braking system).‪

ATI‪

Auxiliary Timed Input‪

ATS‪

Air Temperature Sensor: Monitors engine air temperature.‪

BAT‪

Battery‪

BOI‪

Beginning of Injection: The number of crank angle degrees, before top-dead-center (TDC), where the ECM is requesting the injectors be turned on.‪

BPS‪

Back Pressure Sensor‪

CAN‪

Controller Area Network: J 1939 high speed control data link.‪

CCM‪

Crankcase Monitor Sensor: Monitors crankcase pressure (currently on 149 engines only).‪

CCPS‪

Crankcase Pressure Sensor‪

CEL‪

* Check Engine Light: Typically mounted on the instrument panel. The CEL has two functions: 1. It is used as a warning lamp to inform the operator of the vehicle that a fault has occurred and the unit should be taken in for service as soon as possible. 2. It is used by the operator or technician to "flash out inactive trouble codes to help diagnose a problem.‪

CKT‪

Circuit‪

CLS‪

Coolant Level Sensor: Monitors coolant level at the radiator top tank or heat exchanger.‪

COM‪

Common‪

CPS‪

Coolant Pressure Sensor: Monitors coolant pressure.‪

CTS‪

Coolant Temperature Sensor: Monitors coolant temperature.‪

DDEC‪

Detroit Diesel Electronic Controls‪

DDEC III‪

Third generation Detroit Diesel Electronic Controls‪

DDEC IV‪

Fourth generation Detroit Diesel Electronic Controls‪

DDL‪

DDDL‪

Diagnostic Data Link: The lines (wires) over which the ECM transmits information that can be read by a Diagnostic Data Reader.‪

DDL+‪

DDDL +‪

Data Link, positive side: J 1587 data link.‪

DDL-‪

DDDL -‪

Data Link, negative side: J 1587 data link.‪

DDR‪

Diagnostic Data Reader: The hand held tool used for troubleshooting the DDEC system. MPSI PRO-LINK 9000.‪

DPS‪

Delta-P Sensor – measures a difference in pressure at a given location‪

DRS‪

Distributor Reprogramming Station‪

DT‪

Diagnostic Tool; either DDR (MPSI Pro-Link) or DDDL (PC software used in a similar manner as DDR)‪

ECM‪

Electronic Control Module: The controller of DDEC system. It reads the engine and vehicle inputs, sensors and switches, calculates injector firing and duration, and fires injectors at appropriate times.‪

EEPROM‪

Electrically Erasable Programmable Read Only Memory.‪

EFC‪

Electronic Fire Commander‪

EFPA‪

Electronic Foot Pedal Assembly: Contains the throttle position sensor.‪

EGR‪

Exhaust Gas Recirculation‪

EOP‪

Engine Over-temperature Protection‪

ESH‪

Engine Sensor Harness‪

ESS‪

Engine Synchro Shift‪

EUI‪

Electronic Unit Injector‪

FEI‪

Fuel Economy Incentive‪

FMI‪

Failure Mode Identifier – number used to identify a failure mode‪

FPS‪

Fuel Pressure Sensor: Monitors fuel pressure.‪

FRS‪

Fuel Restriction Sensor‪

FTS‪

Fuel Temperature Sensor: Monitors fuel temperature.‪

GND‪

Ground‪

INJ‪

Injector (fuel)‪

ISD‪

Idle Shutdown: Programmable feature of the DDEC system.‪

IVS‪

Idle Validation Switch: A switch used to establish the idle speed position.‪

LSG‪

Limiting Speed Governor.‪

MAP‪

Manifold Air Pressure‪

MAS‪

Maintenance Alert System‪

MID‪

Message Identification Character‪

MPG‪

Miles Per Gallon‪

N/A‪

Not Applicable.‪

OEM‪

Original Equipment Manufacturer‪

OI‪

Optimized Idle‪

OLS‪

Oil Level Sensor: Monitors oil level.‪

OPS‪

Oil Pressure Sensor: Monitors oil pressure.‪

OTS‪

Oil Temperature Sensor: Monitors oil temperature.‪

PGS‪

Pressure Governor System: Regulates engine speed to maintain a selected external pump pressure.‪

PID‪

Parameter Identifier‪

PING‪

Pilot Injection Natural Gas‪

PTO‪

Power Take-Off. Also, referred to as VSG (Variable Speed Governor).‪

PW‪

Pulsewidth‪

PWM‪

Pulsewidth Modulated: Modulated signal provided by the DDEC system.‪

RES/ACCEL‪

Resume/Accelerate Switch used for cruise control.‪

RH‪

Relative Humidity‪

RHS‪

Relative Humidity Sensor‪

SEL‪

† Stop Engine Light: Typically mounted on the instrument panel. It has two functions: 1. It is used as warning to the operator that a potential engine damaging condition has been detected. If the DDEC system is programmed for shutdown, the engine will shutdown on its own within 30 seconds. The engine should not be run until the condition is corrected. 2. It is used by the operator or technician to "flash" out active trouble codes.‪

SEO‪

Stop Engine Override: Allows the stop engine condition to be overridden in case it is required.‪

SET/COAST‪

Set/Coast Switch: Used in cruise control.‪

SID‪

System Identifier – value used that identifies a sensor or a system‪

SNEF‪

Signal to Noise Enhancement Filter (Module)‪

SRS‪

Synchronous Reference Sensor: Indicates a specific cylinder in the firing order.‪

TBS‪

Turbocharger Boost Sensor: Monitors turbo boost.‪

TBD‪

To be determined.‪

TCI‪

Turbo Compressor Inlet‪

TCO‪

Turbo Compressor Outlet‪

TD‪

Tachometer Driver: An output from the ECM for electronic tachometers and or data loggers.‪

TPS‪

Throttle Position Sensor: Used to detect throttle request (a component of the EFPA). Also, referred to as LSG.‪

TRS‪

Timing Reference Sensor: Used to detect whenever any cylinder is about to be fired.‪

VGT‪

Variable Geometry Turbocharger‪

VIH‪

Vehicle Interface Harness (OEM Wiring)‪

VIN‪

Vehicle Identification Number‪

VNT‪

Variable Nozzle Turbine‪

VOM‪

Volt Ohm Meter‪

VPOD‪

Variable Output Pressure Device – used to accurately position the VNT and EGR valve.‪

VSG‪

Variable Speed Governor. Also, referred to as PTO (Power Take-Off).‪

VSS‪

Vehicle Speed Sensor: Used to detect vehicle speed.‪

VSS OC‪

Vehicle Speed Sensor Open Collector: An ECM input which must be used in addition to the VSS positive input when certain types of vehicle speed sensors are used. Refer to the Application and Installation manual for installation.‪

Table 1. Abbreviations and Terms

* As a light bulb check and system check, the check engine light will come on for about 5 seconds when the ignition is turned on. If the CEL remains on, or comes back on, the self diagnostic system has detected a problem. If the problem goes away, the light will go out, but a trouble code will be stored in the ECM as an inactive code.
† As a light bulb check and system check, the stop engine light will come on for about 5 seconds when the ignition is turned on.


DDEC III/IV Single ECM Troubleshooting Guide - 6SE497
Generated on 10-13-2008

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