E 150 1/2 Ton Van V6-4.2L VIN 2 (1997)
Engine Control Module: Description and Operation
OVERVIEW
The Electronic Engine Control (EEC) system provides optimum control of the engine and transmission through the enhanced capability of the
Powertrain Control Module (PCM). The EEC system also has an On-board Diagnostics (OBDII) monitoring system with features and functions to
meet federal regulations on exhaust emissions.
COMPONENTS
The EEC system has two major divisions: hardware and software. The hardware includes the PCM, Natural Gas Vehicle (NGV) Module, Constant
Control Relay Module (CCRM), Variable Load Control Module (VLCM), 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.
OPERATION
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 scan tool [New Generation Star (NGS), etc.] 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).
