Computers and Control Systems: Description and Operation

Computer Module:

ECM Inputs And Outputs:

SYSTEM DESCRIPTION
The Computer Command Control System has an Electronic Control Module (ECM/PCM). The computer system, through these modules, can monitor a number of engine and vehicle operating functions which control the following systems:

- Fuel Delivery
- Ignition / Electronic Spark Timing (EST)
- Electronic Spark Control (ESC)
- Air management
- Air Conditioning Compressor Clutch
- Coolant Fan
- Engine Speed
- Evaporative Emission Control
- Exhaust Gas Recirculation (EGR)
- Torque Converter Clutch. (TCC)

The computer system has a built-in diagnostic system that recognizes and identifies possible operational problems. The computer system signals the driver through a "SERVICE ENGINE SOON" light located on the instrument panel. The "SERVICE ENGINE SOON" light will remain "ON" until the problem is identified and repaired. This same light is combined with the built-in diagnostic system in order to assist the technician in locating and correcting problems within the system. It does this by flashing a series of codes which identify the possible problem areas at fault, within the computer system. The system also allows for near normal driving conditions during system malfunction, through the use of the built-in backup system. The backup system remains in effect until repairs can be made.