The Basic Engine Computer Control System - Innova 3100 Owner's Manual

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COMPUTER ENGINE CONTROLS

The Basic Engine Computer Control System

The Computer Control System consists of an on-board
computer and several related control devices (sensors,
The on-board computer is the heart of the Computer
Control System. The computer contains several programs
with preset reference values for air/fuel ratio, spark or
ignition timing, injector pulse width, engine speed, etc.
Separate values are provided for various driving conditions,
such as idle, low speed driving, high-speed driving, low load,
or high load. The preset reference values represent the ideal
air/fuel mixture, spark timing, transmission gear selection,
etc., for any driving condition. These values are programmed
by the vehicle manufacturer, and are specific to each vehicle model.
Most on-board computers are located inside the vehicle behind the
dashboard, under the passenger's or driver's seat, or behind the right
kick panel. However, some manufacturers may still position it in the
engine compartment.
Vehicle sensors, switches, and actuators are located throughout the
engine, and are connected by electrical wiring to the on-board
computer. These devices include oxygen sensors, coolant
temperature sensors, throttle position sensors, fuel injectors, etc.
Sensors and switches are input devices. They provide signals
representing current engine operating conditions to the computer.
Actuators are output devices. They perform actions in response to
commands received from the computer.
The on-board computer receives information inputs from sensors and
switches located throughout the engine. These devices monitor
critical engine conditions such as coolant temperature, engine speed,
engine load, throttle position, air/fuel ratio etc.
OUTPUT DEVICES
Fuel Injectors
Idle Air Control
EGR Valve
Ignition Module
INPUT DEVICES
Coolant Temperature Sensor
Throttle Position Sensor
Fuel Injectors
30
switches, and actuators).
TYPICAL COMPUTER
CONTROL SYSTEM
On-Board
Computer
INPUT DEVICES
Oxygen Sensors
OBD 2