|
All modern vehicles have
a computer or the ECM (Electronic Control Module) that controls the
operation of the vehicle power train (the engine and transmission).
The main purpose of this is to keep the engine running at top
efficiency with the lowest possible emissions. With constantly
growing demands for better fuel economy and new strictest emission
regulations it's not very easy to achieve. The engine parameters
need to be constantly and precisely adjusted according to various
conditions such as speed, load, engine temperature, gasoline
quality, ambient air temperature, road conditions, etc. That's why
today's cars have much more electronics than in early days - there
is a large number of various sensors and other electronic devices
that help the vehicle computer or ECM to precisely control the
engine and transmission operation and monitor emissions.
The vehicle computer system has self-testing capability. When the
computer senses that there is a problem with some of the components
it stores the correspondent trouble code(s) in its memory and lights
up the "Check Engine" or "Service Engine Soon" light to tell you
that there is a problem and your car needs to be looked at. To
properly diagnose what is wrong, you need to take your car to Mr.
Transmission or Milex Auto care center. The technician will then
hook up the scanner to the car computer and retrieve the stored
trouble code(s). Then he (she) will look it up in the service manual
provided by a car manufacturer. The service manual contains the list
of possible codes (about few hundreds) and describes what each code
means and what needs to be tested. The code itself doesn't tell
exactly what component is defective - it only indicates where to
look, what engine parameter is out of normal range. The technician
will have to perform further testing to pinpoint a defective part.
|
