DDEC TROUBLESHOOTING Abbreviations Terms DDL Diagnostic Data Link:  The lines (wires) over which the ECM transmits information that can be read by a Diagnostic Data Reader. DDL+ Data Link, positive side:  J 1587 data link. DDL- 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. 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. EOP Engine Over-temperature Protection ESH Engine Sensor  Harness ESS Engine Synchro  Shift EUI Electronic Unit  Injector FEI Fuel Economy  Incentive FPS Fuel Pressure Sensor:  Monitors fuel pressure. 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. 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. All information subject to change without notice. 6SE497  9709  Copyright © 1997 DETROIT DIESEL CORPORATION 4-13