Electronic Engine Control (EEC) System: Overview

The electronic engine control (EEC) system provides optimum control of the engine and transmission through the enhanced capability of the PCM. The EEC system also has an on-board diagnostics monitoring system (OBDII with features and functions to meet federal regulations on exhaust emissions.

The EEC system has two major divisions: hardware and software. The hardware includes the PCM, sensors, switches, actuators, solenoids, and interconnecting terminals. The software in the PCM provides the strategy control for outputs (engine hardware) based on the values of the inputs to the PCM. EEC hardware and software are discussed in this article. This article contains detailed descriptions of the operation of EEC system input sensors and switches, output actuators, solenoids, relays and connector pins (including other power-ground signals). The PCM receives information from a variety of sensor and switch inputs. Based on the strategy and calibration stored within the memory chip, the PCM generates the appropriate output. The system is designed to minimize emissions and optimize fuel economy and driveability. The software strategy controls the basic operation of the engine and transmission, provides the OBD II strategy, controls the malfunction indicator lamp (MIL), communicates to the NGS Tester via the data link connector (DLC), allows for Flash Electrically Erasable Programmable Read Only Memory (FEEPROM), provides idle air and fuel trim, and controls Failure Mode Effects Management (FMEM).