Loading ...
Loading ...
Loading ...
About Diagnostic Systems
WHAT ARE THE ADVANTAGES OF COMPUTER CONTROL SYSTEMS?
11 Chapter 2
WHAT ARE THE ADVANTAGES OF USING COMPUTER
CONTROL SYSTEMS ON VEHICLES?
Vehicle Computer Control Systems can perform millions of
calculations in one second, making them an ideal substitution
for the much slower mechanical engine controls. By switching
from mechanical engine controls to electronic engine controls,
vehicle manufacturers were able to control fuel delivery and
spark timing as well as other engine functions (some newer
Computer Control Systems also control transmission, brakes,
charging, body and suspension systems) more precisely. This
made it possible for vehicle manufacturers to comply with the
new, tougher emission and fuel efficiency standards mandated
by State and Federal Governments.
HOW DOES A COMPUTER SYSTEM WORK ON A
VEHICLE, AND WHAT IS IT’S MAIN PURPOSE?
The main purpose of the vehicle’s Computer Control System is
to provide maximum engine performance with the least
amount of air pollution and the best fuel efficiency possible.
The Computer Control System consists of the on-board
computer, and several related control devices (sensors,
switches, and actuators). 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. Some
manufacturers may still position it in the engine compartment.
The sensors, switches, and actuators are devices such as
oxygen sensors, coolant temperature sensors, throttle position
sensors, fuel injectors, etc., that are located throughout the
engine, and are connected by electrical wiring to the on-board
computer.
The on-board computer is the heart of the Computer Control
System. The computer contains several programs with pre-
programmed reference values for air/fuel ratio, spark or
ignition timing, injector pulse width (how much fuel is injected
into the engine), engine speed, etc., for all possible driving
conditions (idle, low speed driving, high-speed driving, low
load, high load, etc.). The pre-programmed reference values
represent the ideal air/fuel mixture, spark timing,
transmission gear selection, etc., for any driving condition.
These values are programmed at the factory and are specific to
each vehicle model.
2
Loading ...
Loading ...
Loading ...