All You Need to Know About Your Engine Idiot Light
If you have ever owned a car, you've probably experienced
that sinking feeling from seeing the "CHECK
ENGINE" light looming large on the dashboard.
Whether you refer to it as the "Malfunction
Indicator Lamp," "Service Engine Soon
Light" or "Idiot Light," it is
important to understand the basics of this technology.
of the most exciting improvements in the automobile
industry was the addition of second-generation
on-board (OBD2) diagnostics on vehicles. Adopted
as part of a U.S. government mandate to lower
vehicle emissions, this sophisticated program
in the vehicle's main computer system is designed
to detect failures in a range of systems, set
a diagnostic trouble code (DTC) and turn on the
"CHECK ENGINE" light if a problem is
found. All 1996 and newer cars, light trucks and
SUVs have this technology. Not to confuse the
issue, but you should be aware that there is also
OBD1 technology on many 1980s and early '90s makes
and models. This first-generation OBD system monitors
manufacturer-specific systems, but is not universal
like the newer OBD2 technology.
with years of experience don't always go
right to the heart of the problem on the
you turn the key, this light will usually flash
for a second. If the light stays on, your vehicle
may have a problem that ranges in severity from
a loose gas cap, which wastes fuel and causes
pollution, to an engine misfire, which could permanently
damage your vehicle. In any case, there is no
need to panic. It is usually just the vehicle's
computer telling you to get it looked at soon.
the light goes on, most people take their vehicle
to the local mechanic or dealership. There the
technician will connect a scan tool to your car
through an OBD connector that is usually found
under the dashboard. The machine then scans your
car's computer for any DTC, which is used as a
starting point to help determine necessary repairs.
But remember, DTCs and trouble code definitions
are only a starting point. No one — not even a
qualified technician — should ever replace a part
based solely on a trouble code. Even mechanics
with years of experience don't always go right
to the heart of the problem on the first try.
addition to helping with repairs, OBD technology
has recently become even more important. Now that
OBD2 vehicle population is rising, many states
are using OBD2 testing in place of the traditional
tailpipe testing to pass or fail vehicle emissions
or "smog" checks. As of 2004, 33 states
plus the District of Columbia use this technology
for I/M tests, usually required annually or every
contemporary automotive shops, dealerships and
emissions testing facilities invest thousands
of dollars on their scan tool equipment and training
to read complex diagnostic data. This is why they
charge anywhere from $60 to $90 to "scan"
your car, regardless of whether your problem is
a loose gas cap or a severely damaged catalytic
like DVD players and PCs, the longer a technology
is on the market, the more affordable and widely
used it becomes. Thankfully, several automotive
aftermarket manufacturers have developed hand-held
tools called "code readers" that are
much easier to use and more cost effective than
scan tools, but basically do the same thing. Code
readers, which cost as little as $150, are being
used by trained automotive technicians to "quick
check" vehicles before and after repairs.
These same code reader tools are being used by
do-it-yourself mechanics and even consumers who
want to be empowered before going to the mechanic,
taking a long road trip or getting an emissions
readers can save you time and money by locating
and identifying problems before servicing your
vehicle. They let you access the same information
your mechanic has — for less, to help ensure you're
not getting scammed. They can help prevent future
costly repairs and maintain engine performance
with routine inspections. Some code readers even
feature all of the I/M readiness status tests
needed to see if you're ready for an emissions
test. Some OBD2 code readers will even let you
clear trouble codes and turn off your "CHECK
ENGINE" light. But remember, if there is
truly a problem that is more than just an intermittent
occurrence, it will go right back on if you don't
fix what's causing it.
Readers are great tools, but it is important to
remember their limitations. Code readers only
aid in monitoring electronic- and emission-related
faults, so don't forget to check other parts of
the vehicle such as tires, oil level, hoses and
overall soundness before taking a long trip or
conducting a preventative maintenance check.
you are in the market for an automotive code reader,
here are some features to look for and questions
my vehicle have OBD2? OBD2 systems,
also labeled OBD II, are present on all 1996
and newer cars, light trucks and SUVS manufactured
for use in the U.S., plus a few 1995 models.
You can check under the hood for a Vehicle Emissions
Control Information sticker to confirm.
the code reader easy to use?
Look for a tool that is easy to use and doesn't
require a lot of set-up, such as having to input
your Vehicle Identification Number (VIN#) each
time you use it.
I want a PC hook-up?
Depending on your comfort level with computers,
you should know that some code readers offer
PC connections for additional data; others show
you everything you need to know on the tool
itself. Some even have a memory feature so you
can see the DTC after the tool is unplugged
from your vehicle.
the tool include customer support?
Look for a brand that is supported by ASE Certified
technicians who can answer your questions after
you bring it home.
of the easiest-to-use code readers on the market
is the INNOVA® 3100 OBD2 Code Reader. You
don't have to be a mechanic or computer guru to
use this tool. All you do is take it out of the
packaging, plug it into the under-dash connector,
press a button and get all the necessary data
on one screen in about 15 seconds - no set up
required. If any trouble codes come up, you can
access the accompanying manual to define the problem
or bring the code to your mechanic for a second
opinion. What sets this unit apart from other
code readers is its ease-of-use, patented single-screen
display, speed, memory function and affordability.
Sold at more than 5,000 retail and automotive
stores throughout North America, this tool is
used by everyone from professional mechanics and
do-it-yourselfers to consumers and even the California
Air Resources Board (CARB) to test vehicles.
of whether you invest in a code reader or drive
straight to your mechanic, be sure to pay attention
to that "CHECK ENGINE" light. A little
education and preventative maintenance can go
a long way when it comes to preserving the life
of your vehicle and your blood pressure when the
"idiot light" looms large.
in 1982, the company's Equus®- and INNOVA®-branded
test equipment and gauge products are available
at most North American automotive and mass merchandise
retail locations. For information, visit www.iEQUUS.com.
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